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DISPLAY WEEK 2013 REVIEW AND SOLID-STATE LIGHTING ISSUE
Official Monthly Publication of the Society for Information Display • www.informationdisplay.orgSept./Oct. 2013Vol. 29, No. 5
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2 Editorial: A Visionary Destination n By Stephen P. Atwood
3 Industry News: LG and Samsung Bring Large, Curved OLED TV to Markertn By Jenny Donelan
4 Guest Editorial: OLED Lighting Edges Closer to Commercial Realityn By Sven Murano
Display Week Review6 I-Zone and Best-in-Show Winners
The Society for Information Display honored five exhibiting companies at Display Week 2013, the 50thannual SID International Symposium, Seminar, and Exhibition, in Vancouver last May. These companieswere Shinoda Plasma for best prototype in the Innovation Zone and Cima NanoTech, Universal DisplayCorp., E Ink, and 3M for Best-in-Show winners on the exhibit floor.n By Jenny Donelan
8 Touch Technology2013 was a year of evolution and maturation for touch technology, with projected-capacitive dominating theexhibit floor like never before. This article takes a close look at the state of p-cap at the Vancouver show, aswell as at the “Touch-Gesture-Motion” Market Focus Conference at Display Week.n By Geoff Walker
14 LCDsLCDs dominate the display market despite challenges.n By Alfred Poor
20 3-DThe 3-D technology on the show floor this year was represented primarily by small, glasses-free displays withimproved image quality.n By Ken Werner
24 OLEDsTVs were not the only OLED-based products of interest at Display Week. n By Sven Murano and Anke Lemke
28 e-PaperA new product line from E Ink Corp. topped the surprises at this year’s show.n By Jason C. Heikenfeld
31 Venture Capital Series: Part II: Raising Capital for Technology VenturesInvestors come in different packages. It’s important to know the various types, along with their pluses andminuses. This article is the second of four in a series by a venture capital expert who has both launched andfunded new companies.n By Helge Seetzen
Lighting34 Frontline Technology: OLEDs for Professional Lighting Applications
Organic light-emitting diodes (OLEDs) already represent a strong market segment in display applicationssuch as mobile devices. In the lighting market, they are still in the beginning phase. To achieve a relevantmarket segment, OLED technology has to compete in terms of performance, cost, and other unique featuresagainst established light-source technologies. n By Jörg Amelung, Christian Kirchhof, Tino Göhler, and Michael Eritt
38 Frontline Technology: High-Performance White-OLED Devices for Next-Generation Solid-StateLighting The efficacy of white OLEDs has reached 100 lm/W with RGB-phosphorescent emitters and light-extraction technologies. OLEDs have therefore already exceeded the efficacy of typical lighting equipment with fluorescent lamps.n By Kazuyuki Yamae, Hiroya Tsuji, Varutt Kittichungchit, Nobuhiro Ide, and Takuya Komoda
44 Frontline Technology: New Milestones for LED LightingThin-film technology has enabled a new generation of high-brightness LEDsn By Martin Behringer
49 SID News: Display Week 2014 Symposium to Feature OLED TV, Wearable Displays, 3D, andLightingn By Jenny Donelan
52 Sustaining Members and Index to Advertisers
Information Display 5/13 1
SEPTEMBER/OCTOBER 2013VOL. 29, NO. 5
InformationDISPLAYcontents
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INFORMATION DISPLAY (ISSN 0362-0972) is published 6 times ayear for the Society for Information Display by Palisades ConventionManagement, 411 Lafayette Street, 2nd Floor, New York, NY 10003;William Klein, President and CEO. EDITORIAL AND BUSINESSOFFICES: Jay Morreale, Editor-in-Chief, Palisades ConventionManagement, 411 Lafayette Street, 2nd Floor, New York, NY 10003;telephone 212/460-9700. Send manuscripts to the attention of theEditor, ID. SID HEADQUARTERS, for correspondence on sub-scriptions and membership: Society for Information Display, 1475 S. Bascom Ave., Ste. 114, Campbell, CA 95008; telephone 408/879-3901, fax -3833. SUB SCRIP TIONS: Information Display is distributedwithout charge to those qualified and to SID members as a benefit ofmembership (annual dues $100.00). Subscriptions to others: U.S. &Canada: $75.00 one year, $7.50 single copy; elsewhere: $100.00 oneyear, $7.50 single copy. PRINTED by Wiley & Sons. PERMISSIONS:Abstracting is permitted with credit to the source. Libraries are per-mitted to photocopy beyond the limits of the U.S. copyright law forprivate use of patrons, providing a fee of $2.00 per article is paid to theCopyright Clearance Center, 21 Congress Street, Salem, MA 01970(reference serial code 0362-0972/13/$1.00 + $0.00). Instruc tors arepermitted to photocopy isolated articles for noncommercial classroomuse without fee. This permission does not apply to any special reportsor lists published in this magazine. For other copying, reprint orrepublication permission, write to Society for Information Display, 1475S. Bascom Ave., Ste. 114, Campbell, CA 95008. Copy right © 2013Society for Information Display. All rights reserved.
In the Next Issue ofInformation Display
OLED and LCD TVs, Very-High-Resolution Displays, andDigital Signage• Exciting Developments in Digital Signage
• Interactive Digital Signage• Digital Signage and ESLs in Europe• The Metrics of Curved OLED TVs• 4K x 2K: Manufacturing and HumanFactor
• The Perils and Pitfalls of Venture Capitalism
• The Business of Displays in Europe
SIDSOCIETY FOR INFORMATION DISPLAY
DISPLAY WEEK 2013 REVIEW AND SOLID-STATE LIGHTING ISSUE
Official Monthly Publication of the Society for Information Display • www.informationdisplay.orgSept./Oct. 2013Vol. 29, No. 5
Cover Design: Acapella Studios, Inc.
ON THE COVER: Top right: The 2013 I-Zoneaward for “Best Prototype at Display Week” isShinoda Plasma’s film-type display using plasma-array tubes. From lower right, clockwise: Thisyear’s four Best-in-Show winners are: Cima NanoTech’s self-assembling nanoparticle meshtechnology, E Ink’s three-pigment e-paper, 3M’squantum-dot enhancement film, and UniversalDisplay Corp.’s borderless flexible OLED lighting.Background image courtesy of the Vancouver Convention Centre.
ID TOC Issue5 p1_Layout 1 9/22/2013 8:33 PM Page 1
A Visionary Destination
by Stephen Atwood
The 50th annual Display Week event took place in Vancouver,BC, on the beautiful west coast of Canada. Despite a rela-tively long plane ride for many of us, the trip was wellworth it. I arrived a couple of days early so I could get ataste of the local ambiance before the crush of activitiesahead. Vancouver is a beautiful city with an endless arrayof activities. It is very walkable and features some of the
best natural scenery I have ever seen. One example is Stanley Park, which encom-passes about 1000 acres of beaches, rainforest, and hiking trails. I spent most of a daythere, following my own advice from last month about finding balance, and enjoyedsome majestic views along with learning a lot about the local environment. Needless to say, this was truly a visionary destination for Display Week 2013. If
you were one of the lucky ones there then you know what I’m talking about. Theexhibitions of new technology delivered on their promises as did the great paper presentations and seminars. There was a lot to see and do, and as I’ve observed everyyear, it’s more than any one person can absorb. That’s why we bring in a team ofexperts to cover it all for you. So, whether you were there or not, you’ll certainlyvalue the articles we’ve assembled in this annual Display Week review issue. Hope-fully, they will whet your appetite for Display Week 2014 in San Diego, another post-card destination on the west coast of the U.S.In our cover story this issue, Jenny Donelan reports on the winners of the SID Best
in Show awards for 2013. Each year, the award winners are chosen from a select andhighly competitive group of nominees in three categories. The process involves a ded-icated group of industry experts who work incredibly hard to visit the exhibitors, learnabout their latest products and technologies, and then select the very best in each cate-gory. Each of these recipients truly deserves the recognition they have received.No matter where you work in the display industry, you cannot avoid interacting with
touch technology. It’s become an integral part of so many consumer products and acompanion of countless display applications. This year, as our roving reporter and frequent contributing editor Geoff Walker discovered that the touch industry is movingtoward a period of maturation, where almost every mainstream application uses touchin some way. In most cases, that technology is projected-capacitive. Now the industryis looking beyond touch to the next generation of interactive technologies, as we sawso vividly at the Touch-Gesture-Motion Market Focus conference also held at DisplayWeek. Geoff covers it all in his article on touch technology.Of course, LCD technology was dominant in practically every exhibit, as well as the
subject of countless papers and seminar subjects. Despite being ubiquitous, the tech-nology is still evolving rapidly in new directions such as ultra-high resolution, verylarge formats, sunlight readability, and extremely low power configurations. From 5-in. to over 110-in.screen sizes, our contributing editor Alfred Poor has it all coveredfor you in his report on LCDs.Stereoscopic LCDs burst onto the market a few years ago as a strategy to hopefully
boost the sales of new premium TVs. Although the strategy did not play out quite theway manufacturers had hoped, it did generate a new interest for innovation in all typesof 3-D schemes including multi-plane projection, autostereoscopic, holography, andrelated technologies. Many of these were on display at Display Week and long-time
2 Information Display 5/13
Executive Editor: Stephen P. Atwood617/306-9729, [email protected]
Editor-in-Chief: Jay Morreale212/46 0-9700, [email protected]
Managing Editor: Jenny Donelan603/924-9628, [email protected]
Advertising Sales Manager: Joseph Tomaszewski201-748-8895, [email protected]
Advertising Sales Representative: Roland Espinosa201-748-6819, [email protected]
Editorial Advisory BoardStephen P. Atwood, Chair
Azonix Corp., U.S.A.Helge Seetzen
TandemLaunch Technologies, Westmont, Quebec,Canada
Allan KmetzConsultant, U.S.A.
Larry WeberConsultant, U.S.A.
Guest EditorsMaterials
Ion Bita, Qualcomm MEMS TechnologiesOLEDs
Ho-Kyoon Chung, Sungkyunkwan UniversityOxide TFTs
Arokia Nathan, University of Cambridge3D Trends
Nikhil Balram, Ricoh InnovationsTouch and Interactivity
Geoff Walker, Intel Corp. e-Paper and Tablets
Russel Martin, Qualcomm MEMS Technologies Lighting
Sven Murano, Novaled AG Novel Displays
Brian Schowengerdt, University of Washington Very-High-Resolution Displays
David Trczinski, Avid Digital Signage
Terry Schmidt, Christie Digital SystemsAlan Koebel, Christie Digital Systems
Contributing EditorsAlfred Poor, ConsultantSteve Sechrist, ConsultantPaul Semenza, NPD DisplaySearchJason Heikenfeld, University of Cincinnati
InformationDISPLAY
The opinions expressed in editorials, columns, and feature articles do not necessarily reflect the opinions ofthe Executive Editor or Publisher of Information DisplayMagazine, nor do they necessarily reflect the position ofthe Society for Information Display.
editorial
(continued on page 51)
ID Editorial Issue5 p2,51_Layout 1 9/22/2013 1:20 PM Page 2
LG and Samsung Bring Large,Curved OLED TVs to MarketFor those not inclined to head to the beach last summer, there was another option: stayinside and watch big, beautiful OLED TVs.In July, LG made its 55-in. curved OLED TV,first demonstrated at CES last January, available to the public. A few weeks later,Samsung introduced its own 55-in. curved unit.
The stay-at-home option would haverequired deep pockets: at least as of last summer, LG’s TV was retailing for $15,000and Samsung’s for $9,000. Still, the commer-cial availability of these long-awaited TVsrepresents a breakthrough. The sets are nowavailable through Best Buy in the U.S. Information Display contacted a Best Buyrepresentative to find out what customer reac-tion has been thus far, but Best Buy had nocomment. According to the Best Buy Website, the LG unit must be ordered in stores andis only on display in about 20 stores nation-wide. There are no customer reviews postedyet. (Note: At press time, the LG unit went onsale on Amazon for $9,999 and the price waslowered to the same amount on Best Buy.)Consumer Reports recently reviewed the
Samsung unit and was uncharacteristicallygushing about it, saying the test TV performed“brilliantly” and that the technology was apotential game changer. (Consumer Reportshad not yet had the chance to review the LGunit.) Issues such as burn-in and lifetime still have to be tested and addressed, CRcautiously added.1
Many industry experts are scratching theirheads as to why both Samsung and LG choseto introduce OLED TV commercially incurved rather than flat formats. The officialword from the companies is that the curvatureoffers a more enhanced and immersive view-ing experience. Time will tell whether thecurve catches on with consumers.
In the meantime, the OLED TVs keep com-ing and keep getting bigger. At press time,LG had just unveiled a 77-in. UHD curvedOLED TV at IFA 2013 in Berlin. The unitwas a prototype.2
References1http://www.consumerreports.org/cro/samsungoled0813.htm2http://www.engadget.com/2013/09/06/lg-77-inch-curved-uhd-oled/
Microsoft Buys Nokia’s HandsetBusinessIn early September, Microsoft announced thatit was buying Nokia’s smartphone and cellular handset business for $7.2 billion, with $5 billion going toward Nokia’s Devices & Services unitand the other $2.2 billion to license Nokia’spatents and mapping services. The Finnishfirm Nokia is the maker of the Lumia line ofsmartphones, which run Microsoft’s WindowsPhone operating system.
Finland’s flagship company began as apaper mill approximately 150 years ago andwent on to enjoy success in many areas,including rubber, cable, and telecommunica-tions. But Nokia has struggled with mobile-phone sales recently, even as its Lumiasmartphone (winner of a 2013 SID DisplayApplication of the Year Silver Award) waswell received by both critics and consumers.
The acquisition appears to be designed toprovide Microsoft with hardware traction inthe mobile-devices market. Stephen Elop, a former Microsoft employee who becameNokia President and CEO and will now act asNokia Executive Vice President of Devices &Services before returning, post-transition, toMicrosoft as an executive VP,1 spoke aboutthe deal in a Microsoft press release. “Build-ing on our successful partnership, we can nowbring together the best of Microsoft’s softwareengineering with the best of Nokia’s product engineering, award-winning design, and global sales, marketing, and manufacturing…. Withthis combination of talented people, we havethe opportunity to accelerate the current momentum and cutting-edge innovation of both our smart devices and mobile-phone products.”
Going forward, according to a Nokia pressrelease, the agreement stipulates that “Nokiacontinues to develop and sees significantvalue in, advanced technologies, its patentportfolio, and Nokia brand,” and that the com-pany will be “focusing on NSN, HERE, andAdvanced Technologies post-transaction.”The last three are divisions within Nokia.
References1http://en.wikipedia.org/wiki/Stephen_Elop
IFA 2013 HighlightsAt press time, IFA 2013 was taking place inBerlin. In addition to the aforementioned 77-in. OLED TV from LG, the following
display-related products were announced: A 56-in. 4K OLED TV from Sony. The HP Envy Recline, a tablet/laptop
hybrid with a 23- or 27-in. touch screenon a stand that can pivot down off thedesk and over your lap.
4K UHD LCD TVs from Panasonic. 98- and 110-in. UHD LCD TVs from
Samsung, plus an UHD OLED TV. Samsung’s “Galaxy Gear” smart watch.
Projected TouchBy now, most of us have been in the situationof wishing there was a touch interface thatisn’t there – on an iPod Classic, for example,or an ATM window that requires you to pressthe mechanical buttons to the side of thescreen rather than the images on the screen.We seem to want it to be a touch-based world,and a new product from Seattle-based UbiInteractive is designed to help us get there.
With a Kinect sensor, a computer runningWindows 8, a projector, and the Ubi interac-tive software, you can have a touch screen on any surface. The user can interact with the display using simple gestures as if the projected image were a touch screen (Fig. 1).
The Ubi software analyzes the images captured by the sensor to detect the position ofthe user’s hands or fingers in the 3-D space infront of the display. It can precisely deter-mine when the user is in contact with the display and pass this on as a touch event toany touch-ready Windows 8 application. Thesoftware starts at $149 for one touch point andranges up to $1499 for 20 touch points.
Information Display 5/13 3
industry news
Fig. 1: Ubi’s interactive software, when usedwith a Kinect sensor, a computer running Windows 8, and a projector, allows any surface to become a touch screen, as demon-strated at a recent architecture show at California Polytechnic State University.Photo courtesy Ubi Interactive.
ID Industry News Issue5 p3_Layout 1 9/22/2013 1:23 PM Page 3
OLED Lighting Edges Closer to CommercialReality
by Sven Murano
OLED lighting entered the stage about a decade ago withsignificant enthusiasm behind it; however, one cannot failto notice that recently more skepticism can be heard frommarket observers. Despite promising early design studiesand small-sized production campaigns, OLED lighting is
clearly struggling to generate significant sales volume. Even analysts – usually anover-optimistic group – have become rather careful with their predictions for the coming 2–3 years.Does this mean OLED lighting will be stuck in its infancy? Is it already time to
write obituaries for this once-promising technology? Certainly not!There are some very good reasons to be optimistic about the current phase of OLED
lighting and to see it as just a pause in the otherwise very dynamic development of this technology. What seems to be holding back OLED lighting at the moment is competition from inorganic LEDs. LED technology is impressing many with its high-performance levels and constantly decreasing costs. LEDs have garnered a lot of attention from lighting-market players who are still struggling with the adoption ofthe solid-state lighting wave and are looking for solutions that work now.This issue of Information Display features two articles that outline how OLED light-
ing can develop toward commercial success in the coming years – both technology-wise and market-wise. Jörg Amelung from Tridonic gives us an overview of thetechnological features that OLEDs offer and the market segments in which this tech-nology can benefit from these features, which include slim areas emitting diffuse lightsources. The article also states which minimum performance requirements need to befulfilled in order to ensure market entry and which integration difficulties need to besolved. The author also analyzes some devices that are available on the market todayand offers examples of some first applications from different lighting companies.The article from Panasonic’s Kazuyuki Yamae focuses instead on the technological
progress of OLED technology for lighting applications. His team at Panasonic hasmanaged to achieve record-setting efficiency values for OLED lighting panels inrecent years by maximizing the light-extraction efficiencies of the devices. He showsvery nicely the fundamental optical problems that OLED developers must solve anddescribes a solution that was discovered at Panasonic’s laboratories. Finally, he provides an outlook of how efficiency levels should develop in the coming years, inboth R&D and commercial terms.With both articles, you will have a good snapshot of the current state of OLED light-
ing technology, but none of the authors answers the question of when exactly OLEDlighting will make the move into our offices and living rooms. My personal expecta-tion is that the breakthrough is just around the corner. Steady improvements in tech-nological foundations are being made in labs all over the world and all of the bigplayers in Europe and Asia are just waiting for the right moment to ramp up their production. At the same time, several smaller start-up companies are pushing into themarket in a search for their own niches, and this is keeping the bigger guys alert.Lighting designers have developed an initial understanding of this new thing to come,and luminaire makers are therefore beginning to implement OLEDs in their roadmaps.
4 Information Display 5/13
guest editorial
(continued on page 50)
SID EXECUTIVE COMMITTEEPresident: B. BerkeleyPresident-Elect: A. GhoshRegional VP, Americas: D. EcclesRegional VP, Asia: B. WangRegional VP, Europe: P. KathirgamanathanTreasurer: Y. S. KimSecretary: H. SeetzenPast President: M. Anandan
DIRECTORSBangalore: T. RuckmongathenBay Area: J. PollackBeijing: X. YanBelarus: A. SmirnovCanada: T. C. SchmidtDayton: D. G. HopperDelaware Valley: J. W. Parker IIIDetroit: J. KanickiFrance: J-P. ParneixHong Kong: H. S. KwokIndia: Y. MohapatraIsrael: G. GolanJapan: K. KondohKorea: K.-W. WhangLatin America: A. MammanaLos Angeles: L. TannasMid-Atlantic: J. KymissisMid-Europe: H. De SmetNew England: S. AtwoodPacific Northwest: A. AbileahRussia: V. BelyaevSingapore: T. WongSouthwest: S. O’RourkeTaipei: J. ChenTexas: Z. YanivU.K. & Ireland: S. DayUkraine: V. SerganUpper Mid-West: B. Bahadur
COMMITTEE CHAIRS50th Anniversary: L. TannasAcademic: P. BosArchives: R. DonofrioAudit: S. O’RourkeBylaws: T. LoweChapter Formation – Europe: H. De SmetConventions: P. DrzaicConventions – Europe: I. SageDefinitions & Standards: T. FiskeDisplay Industry Awards: W. ChenHonors & Awards: F. LuoI-Zone: J. KanickiInvestment: Y. S. KimLong-Range Planning: A. GhoshMembership: H.-S. KwokNominating: A. AnandanPublications: H. SeetzenSenior Member Grade: A. GhoshWeb Site: H. SeetzenWeb Activities: L. Palmateer
CHAPTER CHAIRSBangalore: S. SambadamBay Area: R. RaoBeijing: N. XuBelarus: V. A. VyssotskiCanada: A. KitaiDayton: J. C. ByrdDelaware Valley: J. BlakeDetroit: S. PalvaFrance: L. VignauHong Kong: M. WongIndia: S. KauraIsrael: I. Ben DavidJapan: K. KondoKorea: Y. S. KimLatin America: V. MammanaLos Angeles: L. IboshiMid-Atlantic: G. MelnikMid-Europe: H. J. LempNew England: J. GandhiPacific Northwest: K. YugawaRussia: V. BelyaevSingapore/Malaysia: C. C. ChaoSouthwest: M. StrnadTaipei: C. C. WuTexas: R. FinkU.K. & Ireland: M. JonesUkraine: V. SorokinUpper Mid-West: P. Downen
SOCIETY FOR INFORMATION DISPLAY1475 S. Bascom Ave., Ste. 114, Campbell, CA 95008408/879-3901, fax -3833 e-mail: [email protected]://www.sid.org
ID Guest Editorial Issue5 p4,50_Layout 1 9/22/2013 1:53 PM Page 4
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ONE of the most exciting aspects of Display Week is all the innovations you willdiscover there. Some products are announcedjust prior to the show, but most attendees,including industry experts, do not really knowwhat the most innovative and interestingexhibits will be until they see them on the showfloor. Both the Innovation Zone (I-Zone) and the Best-in-Show awards were designed to high-light the kind of new and exciting technologythat debuts at Display Week. The 19 exhibitors in the second-annual
I-Zone were chosen to participate on the basisof their cutting-edge research and their abilityto demonstrate a working prototype at theshow. The presence of these companies,many of them start-ups or research arms oflarger institutions, gave show-goers a look atdisplay technologies of the future. Althoughevery exhibitor in the I-Zone was chosen aspart of a competitive process, the winner ofthe Best Prototype award, Shinoda Plasma,demonstrated the best of the best, according tothe panel of experts who selected it.
I-Zone Best PrototypeThis year’s winner of the I-Zone award for“Best Prototype at Display Week” was Shinoda Plasma Co., Ltd., for its film-typedisplay using plasma tube arrays. The display
is actually made of tiny tubes of glass that areeach plasma displays. The tubes are arrangedhorizontally. Although the tubes cannot bend,the carrier on which they are mounted is flexible, so the entire mat of tubes can berolled parallel to their alignment, similar to abamboo window shade (Fig. 1).
Information Display contributing editorAlfred Poor noted that although the moduleshown in the I-Zone had tubes that were 1 mm in diameter, a company representative indicated that smaller 0.5-mm tubes are in development.The tubes are filled with red, green, or bluephosphor and grouped side-by side in threesto create white pixels. The screen in Vancou-ver weighed less than 2 kilos per squaremeter. This technology is currently availablefor large commercial display installations, butthe company has plans for 100-in.-diagonalhigh-definition roll-up models to be used byconsumers in the home. This article is basedon an ID Display Week blog entry by con-tributing editor Alfred Poor.
Best-in-Show WinnersFour companies – Cima Nanotech, UniversalDisplay Corp., E Ink, and 3M – won Best-in-Show awards at Display Week 2013. Thesewere selected by the Display Awards Commit-tee based on the significance of their develop-ment and/or product, for their potential impacton the display industry and consumers of dis-play products, and for their ability to generateexcitement within not only the display indus-try but also the general public and the media.The awards were open to all exhibitors on theshow floor during Display Week 2013 andwere awarded to companies in small, medium,and large exhibit categories. “The selection ofBIS award winners from among the manyexciting new developments presented in the
I-Zone and Best-in-Show WinnersThe Society for Information Display honored five exhibiting companies at Display Week 2013, the 50th annual SID International Symposium, Seminar, and Exhibition, in Vancouver last May. These companies were Shinoda Plasma for best prototype in the Innovation Zone and Cima NanoTech, Universal Display Corp., E Ink, and 3M for Best-in-Show winners on the exhibit floor.
by Jenny Donelan with Alfred Poor
Jenny Donelan is the Managing Editor of Information Display magazine. She can be reached at [email protected].
6 Information Display 5/130362-0972/5/2013-006$1.00 + .00 © SID 2013
I-Zone and Best-in-Show Winners
Fig. 1: Shinoda Plasma’s Best Prototype winner resembles a home movie screen, but itis, in fact, a rollable plasma-based display.Photo courtesy Alfred Poor.
ID Donelan p6-12_Layout 1 9/22/2013 1:59 PM Page 6
exhibits during Display Week is a dauntingand rewarding task that we all take very seri-ously,” says Robert Melcher, chairman of the2013 awards committee.Cima NanoTech for its self-assembling
silver nanoparticle mesh technology (small exhibit): Cima NanoTech’s SANTETechnology is a nanoparticle dispersion that self-assemblesinto a random mesh-like structure when coatedonto a substrate, enabling it to become a trans-parent conductor. Other key benefits are lowsurface resistance (< 25 W/o) at high trans-parency (~88%) and flexibility. Unlike standard metal-mesh technology, the SANTEnanoparticle dispersion’s random network pattern on the surface of a film eliminates the need to orientate the film to a non-moiréposition on a display screen. Markets include EMI shielding, transparent
heating, large-format multi-touch displays,OLED lighting, photovoltaic, electro-chromic,flexible displays, and many more. CimaNanoTech recently commercialized a SANTEproduct line for EMI shielding and transparentheating and a separate line for SANTE touchfilms (Fig. 2).
Universal Display Corp. for its borderlessflexible OLED lighting (small exhibit category): UDC’s all-phosphorescent OLEDlighting panel, built on a plastic substrate system, uses UDC’s proprietary single hybrid-layer UniversalBarrier encapsulation technol-ogy to meet the necessary packagingrequirements for OLED displays and lighting.UDC’s encapsulation also provides completeperimeter coverage for nearly edgeless or“bezel-less” packaging, increasing the panel’sactive area and creating many new productdesign possibilities (Fig. 3).
E Ink for its three-pigment electronic-paper display (medium exhibit category):E Ink Spectra is the first three-pigment elec-tronic ink to be offered in mass productionand was engineered specifically for electronicshelf labels (ESLs). Products using Spectraoffer the same high-contrast, sunlight-read-
able, low-power performance attributes ofmonochrome E-Ink-based display types – butnow with the additional pop of red. The firstgeneration of Spectra will feature black,white, and red pigments, and E Ink says it willrelease additional colors in the future (Fig. 4).By using ESLs with E Ink’s technology,
retailers have the ability to change pricing strategies as needed in real time. Spectra allows retailers to elevate the impact of their ESLs byadding color to logos and quickly directingconsumers’ attention to important informa-tion, such as product sales and promotions.3M for its quantum-dot color enhance-
ment film (large exhibit category): 3M’sQuantum Dot Enhancement Film (QDEF)allows up to 50% more color than current levels in LCD devices. Prior to QDEF, LCDstypically were limited to displaying 35% orless of the visible color spectrum. Wider-color-gamut displays, as enabled by QDEF,will allow consumers to enjoy more visceraland truer-to-life color (Fig. 5).Quantum dots emit light at very precise
wavelengths. This means display makers canuse them to create a highly optimized back-light that produces the exact wavelengths ofred, green, and blue light needed by an LCDfor optimal color and energy performance.Trillions of these quantum dots protected bybarrier film fit inside an LCD backlight unit.The new film replaces one already foundinside LCD backlights, which means the manufacturing process requires no new equipment or process changes for the LCDmanufacturer.3M teamed with Nanosys, Inc., to produce
the 3M QDEF product specifically to delivermore color to devices such as smartphones,tablets, and televisions. n
Information Display 5/13 7
Fig. 3: UDC’s OLED lighting panel is builton a flexible plastic substrate that is all butbezel-less.
Fig. 4: E Ink’s Spectra adds a third color – red – to E Ink’s black and white electro-phoretic display technology.
Fig. 5: 3M’s new QDEF (quantum-dotenhancement film) enables more vivid, true-to-life color for LCDs.
Fig. 2: This scanning electron microscopephoto of SANTE shows the random mesh-likepattern formed by the nanoparticle dispersion.
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AS recently as only 2 years ago, therewere 12 different touch technologies exhibitedat Display Week1; this year, there were onlyfour. Those were projected-capacitive (p-cap,both discrete and embedded, at 21 of the 23exhibitors), analog and/or digital resistive (at 8 of the 23 exhibitors), electromagnetic resonance (EMR) digitizer at one exhibitor, and force-sensing at one exhibitor. That’s a bigchange! The main reason for the change isthe expanded dominance of p-cap. Accordingto DisplaySearch,2 in 2013 p-cap will accountfor 81.4% of units and 92.3% of revenueshipped. Looking at the same data for alltouch technologies by commercial (traditional“vertical markets”) vs. IT/CE (informationtechnology/consumer electronics) products,95.0% of units and 97.0% of revenue will beIT/CE. In other words, it’s all about p-cap,and commercial and industrial applicationsare becoming insignificant in the touch world.
Even with the reduced number of technol-ogies shown, touch was still a big part of theDisplay Week 2013 exhibition. The 23exhibitors mentioned in the above paragraphinclude those showing discrete touch modules,embedded touch, and controllers. In total,there were 63 touch-related exhibitors (35%
of 182 total) at Display Week 2013, as shownin Table 1 below. (Note that many of thematerials exhibitors naturally serve both thedisplay and touch markets.)
Embedded TouchAt Display Week 2012,3 embedded touch wasbig news with the announcement of the firsthigh-volume shipments of hybrid in-cell/on-cell by Sony (now part of Japan Displays,Inc., or JDI). Not unexpectedly, JDI had the
most extensive exhibition of embedded touchat Display Week 2013, with heavy promotionof its somewhat-misleading brand name“Pixel Eyes.” Figure 1 illustrates how PixelEyes is assembled, from both a physical con-struction and a layer perspective.
As an example of its latest innovation, JDI showed a 7-in. 2560 × 1600 (431 ppi)IPS-LCD with Pixel Eyes that was configuredfor use with a passive pen (only). At thatpixel density, anything drawn on the screen
Display Week 2013 Review: Touch Technology2013 was a year of evolution and maturation for touch technology, with projected-capacitivedominating the exhibit floor like never before. This article takes a close look at the state of p-cap at the Vancouver show, as well as at the “Touch-Gesture-Motion” Market Focus Conference at Display Week.
by Geoff Walker
Geoff Walker is a Senior Touch Technologistat Intel. He has also been Information Display’sGuest Editor for Touch & Interactivity since2007. He can be contacted at [email protected], 408/765-0056 (office) or 408/506-7556 (mobile).
8 Information Display 5/130362-0972/5/2013-008$1.00 + .00 © SID 2013
touch-technology review
Table 1: There were 63 touch-related exhibitors at Display Week 2013; 23 (36%) showed touch modules, controllers, or embedded touch;
22 (35%) showed touch materials or related processes and technology; and 18 (29%) showed touch displays, integration, enhancements, or market research. In this analysis, each exhibiting company is
counted only once, even though it could be in multiple categories.
Product Category Exhibitors Product Category Exhibitors
Modules 15 Bonding 2
Enhancements 8 Glass processing 2
Adhesives 6 Market research 2
Metal & CNT films 5 EMR digitizer 1
Touch displays 5 Haptics 1
Controllers 3 Laser patterning 1
Embedded touch 3 Multi-touch self-capacitive 1
Glass 3 Pressure-sensing tiles 1
Integration 3 Passive styli 1
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was rendered with exquisite sharpness. Theentire display was only 1.78-mm thick,including the cover glass. JDI was also show-ing its version of OGS (one-glass solution),which it calls “Sensor on Cover Lens” (illustrated in Fig. 2).
LG Display (LGD) showed hybrid in-cell/on-cell embedded touch in a 7-in. LCD, wherethe drive electrodes were on the oxide-TFTglass (the same as JDI) but the sense electrodeswere on a PET film laminated between thecolor-filter glass and the cover glass. LGDnamed this configuration “F1T”, a creativemodification of the current p-cap layer-construction abbreviation format. The signageshown with the display allowed an observer tocalculate that 40 VCOM electrodes are grouped to form each of 32 drive electrodes. The signage also specified a minimum passive-stylus tip diameter of 2.5 mm, which is not quite as good
as the typical 1.8–2.0 mm currently beingspecified by the top touch-controller suppliers.Unfortunately, the touch performance of thedisplay was very erratic. The booth staff sug-gested that the problem was too much electro-magnetic interference (EMI) at the show. Ifso, I look forward to better demonstrations inthe future when they work this out.
The third display manufacturer showingembedded touch was Innolux. In a change ofstrategy from last year’s “we supply all formsof embedded touch” exhibit, Innolux this year showed only on-cell in many differentdisplays, including a 4.5-in. 1280 × 720 (330 ppi) 2-D/3-D LCD. When questionedabout this change, booth staff said thatInnolux had decided to “keep LCD yields ashigh as possible” by building the completecell, including glass thinning, and then addingthe touch screen. This approach results in
lower-quality ITO, since high-temperatureannealing cannot be done on a completed cell.Innolux explained that its business prioritywas to keep LCD cell yields at maximum, andtherefore it had to accept some performancecompromises in touch implementation. Thispositioning was emphasized (perhaps inadver-tently) by Innolux in its 39-in. touch displaymade with ITO in a diamond pattern at 50 W/sq.The ITO in this display (shown in Fig. 3) wasso visible that it almost seemed to be part ofthe image.
In another change of strategy from lastyear’s exhibit, Innolux did not make any useof its “Touch On Display (TOD)” brand.While the company confirmed that the branddoes cover all forms of embedded touch (in-cell, hybrid in-cell/on-cell, and on-cell),booth staff said that Innolux is only using thebrand “with customers.”
Projected CapacitiveShowing off its expertise in high-performancelarge-format p-cap, 3M Touch showed a prototype of its latest 55-in. touch-displaytable. It truly was a prototype; underneath the table was a standard laptop strapped to astandard NEC LCD.
AMTouch USA (part of AMT-Taiwan)showed a 21.5-in. p-cap touch display withsurprisingly good performance. In part, thisperformance is due to AMTouch doing itsown controller firmware so it can provide better support to commercial customers.AMTouch is not the only supplier using thisstrategy; another on the exhibit floor wasUICO. In UICO’s case, the primary reasonfor doing its own controller firmware is tooptimize for industrial-application conditionssuch as water and gloves. A supplier (also onthe exhibit floor) taking the opposite strategyis Ocular; instead of doing its own firmware,Ocular partners very closely with Atmel tooptimize for industrial-application conditions.
While visiting the Panjit (Mildex Optical)booth, this author was able to take a picture of the wide variety of sensors being shown.Figure 4 shows a stack of seven Panjit p-captouch screens. This is actually a good exam-ple of the large quantity of touch-screen hard-ware that is available for close inspection onthe exhibit floor.
Other Touch TechnologiesAs noted in the introduction to this article, theonly other technology shown in any quantity
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Fig. 1: JDI’s (formerly Sony’s) “Pixel Eyes” hybrid in-cell/on-cell embedded touch is shownfrom both a physical construction (left) and a layer perspective (right). For a more detailedexplanation of how it works, see Ref. 3. Source: Artwork by JDI; annotation on left by theauthor.
Fig. 2: JDI’s version of OGS (one-glass solution), called “Sensor on Cover Lens,” is comparedwith conventional discrete (“outcell”) touch-sensor construction. Note that the total thicknessreduction gained through OGS is only 150 µm. Source: Artwork by JDI; annotation by theauthor.
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on the exhibit floor was analog and/or digitalresistive. Of the eight exhibitors, the best inthe author’s opinion was Fujitsu. The reasonis that it was best able to clearly communicateits differentiation in terms of features as follows:
4-, 5-, 7-wire and “gesture-touch” types Pinch, rotate, flick, and swipe gestures 10-finger multi-touch via digital resistive Film-glass and film-film-plastic con-
struction Very low activation force (“Feather
Touch”) Drivers for Windows, Linux, and
Android USB, serial, I2C, and SPI interfaces Gorilla glass and plastic substrates Anti-glare or clear finishInstead of saying (in effect) “we sell resis-
tive touch; everybody knows what that is,” thecompany painstakingly identified its advan-tages and engaged visitors with demos that fit the audience such as digital resistive formilitary applications.
There actually was one additional touchtechnology on the exhibit floor, but it wasn’tidentified as such. Bi-Source (BSI), a touch-display maker, used a 72-in. touch displaywith traditional infrared as an attention-getterfor its booth. The author is fairly sure that itwas the only IR touch screen on the entirefloor.
Other Interesting BitsTouch is so well-integrated into Display Weekthat you really have to walk the entire show inorder to see everything that’s touch-related.Exhibits of particular interest included Fogale,Cima NanoTech, Canatu, and Samsung Display.Fogale, based in France and exhibiting in theInnovation Zone, was showing “multi-touch/multi-touchless self-capacitive.” In thesetimes of pervasive mutual-capacitive p-cap,self-capacitive is not something that’s seenfrequently. Fogale’s technology uses an“active guard” to totally eliminate all parasiticcapacitance, allowing measurement of 0.0001pF between an electrode and the target (this is100× better than what’s possible with currenttechnologies). This active-guard approachisolates a sense electrode (or an entire circuit)from ground, thus eliminating the effect of the parasitic capacitance between the senseelectrode and ground. It works by applying asinusoidal signal to the sense electrode; thisallows measurement of the current flowingthrough the parasitic capacitance between asense electrode and ground. An exactly equalsignal is applied to a guard electrode that sur-rounds the sense electrode. Because the senseand guard electrodes are at the same potential,the leakage current from the sense electrode to ground is reduced to essentially zero, thuseliminating the effect of the parasitic capaci-tance.
Fogale is initially focusing its technologyon smartphones and tablets; it supports fivetouches on a 5-in. screen and 10 touches on a10-in. screen. When the user’s hand is hover-ing above the screen, Fogale supports recogni-tion of individual fingertips at up to 5 cm, andthe whole hand at up to 8–10 cm. Accuracyand linearity are better than 1 mm. Figure 5shows a block diagram of Fogale’s controllerwith a red dotted line around the portions thatare isolated by the active guard. Note that theleakage capacitance shown in the drawing isin terms of attofarads (1×10-18 farads).
Cima NanoTech is a relatively new entrantin the ITO-replacement materials market; itwas showing a “self-assembling silver mesh.”Cima’s material starts as an opaque liquidthat’s coated on film using industry-standardequipment; 30 sec later the liquid dries into arandom-pattern silver mesh with 5-µm con-ductors and 150–300-µm open spaces – verysimilar to the characteristics of printed metal-mesh material. This product received a Best-in-Show award at Display Week.
Canatu, based in Finland and exhibiting inthe Innovation Zone, was showing a new formof carbon nanotubes (CNTs) called CarbonNanoBuds. These are yet another new trans-parent conductor (i.e., ITO-replacement)material consisting of carbon nanotubes with abuckyball (fullerene) attached. Canatu claimsthat the addition of buckyballs to some CNTs
touch-technology review
10 Information Display 5/13
Fig. 3: Innolux’s 39-in. touch display was made with ITO in a diamond patternat 50 Ω/sq. The right-hand photo is a close-up of the area outlined in red in the left-hand photo. The ITO is so visible it almost seems like part of the image. Source: Author photo.
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makes the material much more able to com-bine with other materials due to some bucky-balls having only five carbon atoms ratherthan CNT’s six-atom structure. In theauthor’s opinion, Canatu’s real breakthroughis its “NanoBud Reactor,” which takes trans-parent film and carbon gases as inputs andoutputs a patterned touch sensor made withrelatively uniform length and relatively pureCNTs. Solving the problems of length andpurity in a single manufacturing process issomething that the rest of the CNT industryhas not been able to accomplish yet.
Finally, among many other things, SamsungDisplay showed a 23-in. “metal-wired touch”display with a plastic cover lens. The touchmodule was constructed of poly-methylmethacrylate (PMMA) with an OCA-attachedfilm-sensor (made of either metal mesh or silver nanowire; it wasn’t clear which). ThePMMA cover glass was particularly nice, withanti-glare, a very good touch feel, and 5Hhardness. Unfortunately, the touch perform-ance (rated for 10 touches) was not as good asit could be; the system tended to drop touchpoints when 10 touches were moving at highspeed. It may have just been over specified,since the system performed acceptably withtwo or three touches at moderate speed.
Summary of Observations from theExhibit FloorThe following are the author’s observationsafter studying the exhibits:
In previous years, the number of touchmodule-makers exhibiting usuallyexceeded the number of touch-materialsmakers; in 2013, they were roughlyequal.
At least for Display Week, p-cap hasknocked out almost all other touch tech-nologies except resistive.
Embedded touch in all forms (in-cell,hybrid in-cell/on-cell, and on-cell) isgrowing.
ITO replacements, especially metalmesh, are growing.
Enhancements such as top-surface coat-ings, filters, and bonding are very impor-tant in commercial applications.
In general, Display Week touchexhibitors tend to appeal more to com-mercial users than consumer users.
Even though p-cap is overwhelminglydominant, innovation in touch continues.
Market Focus ConferenceWednesday’s all-day “Touch-Gesture-Motion”(TGM) Market Focus conference (producedby IHS in cooperation with SID) consisted of23 presentations focused on next-generationtouch-, gesture-, and motion-based technolo-gies applicable to the display industry. In theauthor’s experience, presentations at busi-ness/technology conferences such as this canbe classified into three groups: market or tech-nology forecasts, product or company pitches,and truly thought-provoking presentations thattranscend either of the first two. The first cat-egory is straightforward, usually consisting oftalks by analysts and technologists (includingthe author). The challenge for all speakers atbusiness/technology conferences is to land inthe third category; the realities of marketingand business typically force many (or most)speakers into the second category.
At this TGM conference, there were fourpresentations that the author found trulythought-provoking; they were by York University, Sensor Platforms, Elliptic Labs,and Qualcomm. Wolfgang Stuerzlinger, aprofessor at York University in Toronto,Canada, presented “Is ‘Iron Man 2’ Right?Re-Investigating 3D User Interfaces.” 4Beginning with a video clip from the movie
Iron Man 2, showing superhero Tony Starkcommanding a “floating-in-the-air” 3-D user-interface (UI), Wolfgang’s presentation arguedthat while floating objects look cool inmovies, they do not exist in reality and aretherefore a poor basis for a 3-D UI. Wolfgangalso showed results from several studies thatmeasured the throughput achieved with a varietyof 2-D and 3-D pointing and touch methods,with the general conclusion that as the dis-tance from the target increases and/or as 3-Dviewing is added, throughput goes down. Inother words, it is tough to beat the good oldmouse, even for manipulating 3-D objects!During his presentation, Wolfgang noted thatin his opinion, the “Iron Man” trilogy shouldbe required viewing for students of 3-D UIs(along with, of course, Minority Report) – primarily as examples of what not to do!
Kevin Shaw, CTO of Sensor Platforms, pre-sented “Context Awareness Using Sensors.”Kevin defined context as “a framework thatprovides understanding of an event.” Contextis transitory, multivariate, and personal; it isnot a gesture or a picture; and it must work foreveryone all the time. Kevin used a numberof common activities to illustrate the value ofcontext; these included answering the phone,going to a meeting, reaching for toothpaste,
Information Display 5/13 11
Fig. 4: This stack includes seven Panjit (Mildex Optical) p-cap touch screens. Source: Authorphoto.
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driving home, visiting your doctor, teaching aclass, and monitoring the driving behavior ofyour teenage daughter. He then used the anal-ogy of human senses and the brain to makethe point that mobile devices equipped with(a) a variety of hard and soft sensors (heshowed a list of 16), (b) sophisticated algo-rithms, and (c) always-on sensing (i.e., contin-uous measurement) can become context platforms that enable a new class of smartmobile apps. In closing, Kevin showed thepower consumption of 10 common sensorsthat ranged from 5 µA to 75 mA, making thepoint that designing for low power is the pre-eminent challenge in achieving his visionof “context platforms.”
Tobias Dahl, the founder and CTO of Elliptic Labs, presented “Touchless Ultra-sound Gestures – from Physics to Use Cases.”Tobias’s presentation explained in detail howultrasound can be used as a rich gesture-recognition platform technology. Tobiasstarted with the physics of ultrasound: (a) therelatively slow speed of sound allows accuratedetermination of relative motion even withlow bandwidth and only a few sensors and (b)the wide field of view created by diffractionallows sensing movements far away and upclose, with a 180° field of view. Next,describing features derived from the physics,Tobias explained that it is easy to create adepth filter using ultrasound because ultra-sound derives (x,y) position from multiple-range (z) measurements, while stereoscopic
optics derives z from multiple correlated (x,y)positions. Finally, Tobias described nine categories of gestures that can be used withmobile devices, and five uses cases – includ-ing how ultrasonic-sensed gestures could beused to play Angry Birds.
Francis MacDougall, Senior Director ofGesture Technology at Qualcomm, presented“Touch-Free Gestures for Next-Gen UX.”Francis’s presentation focused on the emerg-ing use of gestures in mainstream consumer-electronics devices. He used, as an example,the Samsung Galaxy S4, analyzing the func-tionality of its five “air gestures,” as well asthe use-case for hover in five applications.Francis pointed out that hover is now avail-able in touch controllers from Cypress andSynaptics and that hover is a standard part of Android, implemented seamlessly withother touch-screen event handling. Next,Francis summarized the common near- andfar-field gestures in use today and described amethod of adding gestures to existing applica-tions through the use of a “gesture layer.”After summarizing some current and soon-to-be available hardware, Francis closed withthree pieces of advice to device-makers: (a)focus on using gestures to enable user experi-ences that go beyond touch by speeding upspecific tasks, (b) rapid UI feedback for alltouch-free interactions is essential, and (c)expect higher-fidelity gestures using emergingtechnologies (such as ultrasound) in the next12 months.
The astute reader may say, “Wait a minute!The last three of those presentations soundedsuspiciously like product pitches!” True,every presentation by a commercial enterpriseother than market or technology forecasts arebasically product or company pitches at heart.What separates the wheat from the chaff is ifafter a presentation I feel more knowledgeable(educated), I’m excited about future possibili-ties, and I find myself thinking hard abouthow what I just heard fits into my view of theworld.
Touch in Depth and BreadthOnce again, there was an amazing amount oftouch technology at Display Week 2013. Thisis especially clear when one considers theadditional touch resources at Display Weekbeyond the exhibits, including the 13 Sympo-sium touch papers, the Sunday Short Courseon touch, the two Monday Seminars on touch,the six Exhibitor’s Forum touch presentationson Tuesday, the 23 presentations at Wednes-day’s Market Focus “Touch-Gesture-Motion”conference, and, finally, the seven Touch andInteractivity posters presented in Thursday’sPoster Session. It is these additional resourcesthat differentiate Display Week from any othertouch conference worldwide. While Asiantouch exhibitions such as Touch Taiwan5 (inTaipei) or C-Touch6 (in Shenzhen) may havemore exhibits by touch module and materialsuppliers, no other conference has DisplayWeek’s depth and breadth of presentations ontouch. If you are involved in the touch indus-try, you just can’t afford to miss Display Week2014 in San Diego. Start planning for it now.
References1http://informationdisplay.org/IDArchive/2011/JulyAugust/TouchTechnology.aspx 2DisplaySearch, “Quarterly Touch Panel Market Analysis Report” Q2-2013.3http://informationdisplay.org/IDArchive/2012/September/DisplayWeek2012ReviewTouch-Technology.aspx 4An earlier version of Professor Stuerzlinger’spresentation can be viewed as a 27-minuteTEDx video at http://www.youtube.com/ watch?v=3Q3Pft-xA0Y.5http://www.touchtaiwan.com/en/ 6http://www.chinaexhibition.com/Official_Site/11-3311-C-TOUCH_2013_Shenzhen_- The_11th_China_(Shenzhen)_International_Touch-screen_Exhibition.html n
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Fig. 5: A block diagram of Fogale’s “multi-touch/multi-touchless self-capacitive” controllershows the components that are shielded with an “active guard” surrounded by a red dotted line.Source: Excerpted from Fogale’s Exhibitor Forum presentation.
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HERE’S A MYSTERY: liquid-crystaldisplays (LCDs) dominate just about everyinformation-display application worldwidethese days. Yet, to paraphrase WinstonChurchill’s famous quote about democracy,LCDs are the worst form of display technol-ogy except for all the others that have beentried.
Consider the following: It is a fussy tech-nology that requires a complex switchingbackplane. It is not a solid-state solution; itactually requires that some components physi-cally change their location and orientation inorder to work. And it is dreadfully inefficientin that a typical active-matrix LCD consumes95% or more of the transmitted light, evenwhen it’s showing a pure-white image. As aresult, you have to use very bright backlights,which, in turn, require complex light recoveryand management components to make effi-cient use of this energy.
Yet, despite of all this, LCD technologyremains without question the dominant electronic-display technology in the world.Nowhere was this more evident than at SID’sDisplay Week 2013 in Vancouver, BritishColumbia, Canada, last May. From theExhibit Hall to the Symposium, it was clear atevery turn that LCD technology have an enor-mous lead over all other display technologies,
and this situation is not likely to change soon.It is true that cathode-ray tubes (CRTs) onceheld a similar lead that seemed insurmount-able, but current competing technologies arenot gaining much traction, while LCDs con-tinue to improve. Organic light-emitting-diode (OLED) displays are starting to buildout from their beachhead in the mobile-devicemarket, but they remain a small factor in theoverall numbers. Reflective and bistable displays continue to evolve and have hadsome success in niche segments, but show little sign of competing in any significant wayin broader markets. The fact remains thatLCD technology continues to improve – andcosts continue to fall – faster than the levelsachieved by competing technologies. Thismakes it difficult for any alternative to mounta serious challenge.
LCD industry revenues are forecast to groweven as the unit prices of the products con-tinue their steady decline. As was pointed outby Sweta Dash from IHS at the Display WeekBusiness Conference, LCDs will generatemore than $120 billion in market value thisyear, a figure that will climb to more than$150 billion by 2017 (Fig. 1).
More PixelsWhile there were many interesting improve-ments in LCD technology in evidence at Display Week 2013, one clearly stands outfrom the rest. The trend toward “4K” resolu-tion displays is gaining momentum, whichwas evident just about everywhere you turnedat Display Week.
For example, Mike Lucas, Senior VP ofSony’s Home Entertainment and SoundGroup, addressed the Business Conference
with a presentation on “4K: The ResolutionRevolution.” Citing nearly 75% penetrationof HDTVs in the U.S. and a move to larger setsizes, he made the case for increasing resolu-tion on TVs to 4K resolution (four times thepixels of HDTV). More than 15,000 digitalcinemas already have projectors with 4K reso-lution, more than 100 feature films have beenreleased in 4K, services including Netflix aredeveloping prototype streaming services for4K content, and Sony has a 4K media playerthat can download new content from the Internet. Clearly, many manufacturers arehoping that 4K will revive flagging interest innew televisions and help shorten the replace-ment cycle for consumers.
A 4K LCD was the recipient of one of theSID Display Industry Awards this year. The110-in. LCD TV from Shenzen China StarOptoelectronics Technology (CSOT) won theSilver Award in the Display of the Year cate-gory. This model also supports 3-D TV usingactive-shutter glasses, incorporates multi-touch technology, and has a dynamic back-light to boost contrast performance.
Other 4K LCDs were on display in theExhibit Hall. Samsung showed its giant 85-in. prototype (Fig. 2) and LG showed itsnearly as enormous 84-in. screen (Fig. 3).
New technologies are also bringing thesehigh-resolution images to smaller screens.For example, the metal-oxide IGZO back-planes have higher electron mobility than thestandard amorphous-silicon (a-Si) backplanes,which makes it possible to create smaller transistors for the active-matrix backplanes.Sharp was showing a 31.5-in. LCD panel thatoffers 4K resolution using an IGZO backplane(Fig. 4).
Display Week 2013 Review: LCDsLCDs dominate the display market despite challenges.
by Alfred Poor
Alfred Poor is a Senior Member of SID andContributing Editor with Information Displaymagazine. A speaker and writer with an inter-national reputation, he has followed the dis-play industry for decades, yet still gets excitedby the improvements in display technology.He can be contacted by e-mail at [email protected].
14 Information Display 5/130362-0972/5/2013-014$1.00 + .00 © SID 2013
LCD review
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Smaller PixelsIn fact, the fabrication of smaller and smallerpixels is another area where LCD technologyhas been advancing. With the ever-growingconsumer interest in smartphones and tablets,manufacturers are seeking to increase resolu-tion as a differentiating feature. Smaller pixels mean that a panel has more pixels per inch. Inorder to create an active-matrix display, eachpixel must have at least one transistor switch.These switches have to be small enough to letsome light through (the aperture ratio), so the development of backplanes that support smaller semiconductor devices is a primary driver for higher resolutions. There were many examples of displays with small pixel structures through-out the exhibit hall. For example, Samsungshowed a new 13.3-in. LCD panel with anamazing 3200 × 1800-pixel resolution, whichworks out to 276 pixels per inch (ppi).
That pales by comparison to the one thatInnolux was demonstrating. Its full HD (1920 × 1080-pixel resolution) panel was only5 in. on the diagonal. Using low-temperaturepolysilicon (LTPS) TFTs for the backplane,the panel was able to display 444 ppi. This isall the more impressive because each pixelwas composed of four subpixels – red, green,blue, and white – and the display also had apanel border of just 0.5 mm.
Smarter PixelsLCD pixels are not just getting smaller, theyare getting smarter, too. Sharp showed its
Memory LCD panels that have one bit ofmemory embedded in each pixel of the monochrome (black and white) displays (Fig. 5). This makes it possible to greatlyreduce the power consumption required to
maintain an image compared with conven-tional LCD designs. Some models aredesigned to run on 3-V dc power supplies,making them compatible with standard “button” batteries.
Information Display 5/13 15
$160,000
$140,000
$120,000
$100,000
$80,000
$60,000
$40,000
$20,000
$02010 2011 2012 2013 2014 2015 2016 2017
Source: IHS Inc.
TVsTVs
OtherOther
Valu
e (M
illio
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Mobile Handset
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Fig. 1: According to IHS, LCD worldwide revenues are forecast to continue to rise in the near future, despite stagnating television sales anddeclining unit prices in general. (Source: IHS)
Fig. 2: Samsung was one of the major display makers showing products that raised the bar forLCDs, including this 85-in. 4K panel. (Photo credit: Alfred Poor)
ID Poor p14-18_Layout 1 9/22/2013 4:34 PM Page 15
Pixels are getting smarter in other ways aswell. Working in partnership with Nanosys,
3M announced its new Quantum DotEnhancement Film (QDEF). The quantum
dots can convert light of one wavelength toanother, and they can be tuned to produce avery narrow range of wavelengths, whichresults in precise colors. In turn, this greatlyincreases the color gamut that LCD panels candisplay. The film takes the place of anotherfilm already used in LCD backlights, whichmeans that no production changes are requiredto use this material with existing panels. (3Mwon a Display Week 2013 Best-in-Showaward for this product.) Quantum dots arealso used by the Color IQ material made byQD Vision. This is used in select models ofSony’s BRAVIA LCD-TV product line andhelps increase the color gamut of the display.Color IQ received the Gold Award for the SIDComponent of the Year, which was presentedat Display Week 2013.
Many Kinds of PixelsThese examples just scratch the surface of theLCD products shown at Display Week 2013.Some had unusual shapes or configurations.For example, Kyocera showed a 2.5-in. roundLCD with a 240 × 240-pixel resolution. JapanDisplay Inc. (JDI) had a rectangular LCDpanel designed for use in an automotiveinstrument cluster. This panel had a hole inthe middle that would accept the shaft of aconventional mechanical indicator. The resultis that automobile engineers can designgauges that can provide different displaysusing a physical pointer. JDI also had amockup of a car’s dashboard using curved andcircular LCDs (Fig. 6).
Other automotive panels were also in evi-dence, such as Kyocera’s rearview-mirror display, which is already in production.
An area of specialization to note is high-brightness displays, which include sunlight-readable modules for use everywhere, fromavionics to bank ATMs. LG had a panelintended for digital-signage applications thatboasted a luminance of 2000 nits (candelas/square meter). MacroDisplay, Inc., demon-strated a novel approach to sunlight-readabledisplays by using its directional light-guidingfilm (DLGF). This allows an LCD panel toemploy both a backlight and a bright ambientlight as an illumination source, so that thesame panel can be used in daylight and indoorsettings. BrightView Technologies offers avariety of high-brightness solutions and wasshowing a choice of cold-cathode fluorescent(CCFL) and light-emitting-diode (LED) back-lights. The company also provides dimmable
LCD review
16 Information Display 5/13
Fig. 3: LG also is helping to bring the “big screen” to living rooms worldwide with its 84-in.4K LCD panel. (Photo credit: Alfred Poor)
Fig. 4: Sharp’s 31.5-in. LCD panel relies on an IGZO metal-oxide backplane to deliver 4K resolution. (Photo credit: Alfred Poor)
ID Poor p14-18_Layout 1 9/22/2013 4:34 PM Page 16
panels, so the same display that is suitable forhigh levels of ambient light can also bedimmed for nighttime viewing. MitsubishiElectric Corp. and Santek were among otherLCD-panel providers offering high-brightnessproducts.
In addition to all these, there was a nearlyendless assortment of panels for industrialapplications and other uses. One interestingdevelopment is that nearly all the LCD panelsoffered now use LED backlights instead ofCCFLs. Many of the manufacturers and vendors provide support for their clients whowant to switch from CCFLs to LEDs for thepanels used in their products. EndicottResearch Group (ERG) specializes in this area and was showing a number of power-conversion products and drivers for LCDbacklights at Display Week. Renesas Electronics America showed a wide variety of panels from NLT Technologies, primarilyfocused on value-added solutions for lower-volume applications. This company is affili-ated with Tianma Microelectronics, whichshowed a range of high-volume solutions.These included panels with integrated projected-capacitive (p-cap) touch, displaysfor outdoor viewing that use transmissive orreflective technology, and panels for specificpurposes such as medical applications.
Moving ForwardIf the Symposium is any measure of overallinterest in improving LCD technology, thefield continues to advance. Only the subjectof 3-D displays had more sessions devoted toit than liquid crystals and related topics. Ifyou added the sessions on TFT and metal-oxide semiconductor research, LCD topicsoutnumbered them all. Perhaps the mostintriguing session of all was Session 5, whichpresented three different views of the compe-tition between LCD and OLED technology fordisplays, especially in the mobile-device market. The strong indication is that OLEDtechnology is not likely to mount a seriouschallenge to LCD dominance, at least for theshort term. Industry-analyst David Barnes ofBizWitz gave a compelling analysis that pre-dicts that no matter which technology winsout, it is the consumer who will likely gain allthe benefit of the competition. Yasuhiro Ukaifrom the Ukai Display Device Institute tookthe position that LCD dominance is likely tocontinue, although there is room for improve-ment in manufacturing efficiency. And Joun
Ho Lee and colleagues from LG Display presented a comparison of LCD and OLEDperformance in mobile displays, showing thatLCDs have some specific advantages for resolution, contrast ratio, and color.
The LCD industry is an industry with anapparently insurmountable lead in many market segments. Part of the reason for thisstatus, despite the technology’s aforemen-tioned shortcomings, is that the researchers
Information Display 5/13 17
Fig. 5: This tiny LCD panel from Sharp includes memory for each pixel, which greatly lowerspower consumption. (Photo credit: Alfred Poor)
Fig. 6: This curved automotive dashboard from JDI demonstrates the many ways that LCDscan be adapted to bring new functionality to existing applications. (Photo credit: Alfred Poor)
ID Poor p14-18_Layout 1 9/22/2013 4:34 PM Page 17
and the companies behind LCDs are not com-placent. Competing technologies keep step-ping up to challenge LCDs in one segment oranother and before they can do so, LCD tech-nology raises the bar. Think of OLED tech-nology’s edge in terms of color, contrast, andpanel thickness and how every year, LCDsimprove so as to lessen that edge on all threecounts. Display Week 2013 clearly demon-strated that liquid-crystal technology contin-ues to provide the best value for manyapplications by combining excellent perform-ance with low cost, and that everyoneinvolved in the industry continues to investtime and money to make these displays moreversatile and powerful than ever. n
LCD review
18 Information Display 5/13
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ID Poor p14-18_Layout 1 9/22/2013 4:34 PM Page 18
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THE topic of 3-D did not have a promisingstart at SID’s Display Week 2013. In his key-note address, Bill Buxton of Microsoft Research said, “3-D [television] was a demonstrably bad idea before it even started.” He was referringto the industry’s hope that 3-D could enable anew generation of high-margin products thatwould induce customers to replace the largelycommoditized 2-D LCD and plasma TVs they had already bought. Said Buxton: “Itdidn’t work out that way.”
It is widely accepted that 3-D TV is all butdead in the North American market, and threeweeks after Buxton made his comment, ESPNput a large additional nail in the coffin byannouncing it would discontinue its ESPN 3-D sports channel by the end of this year.
Large-Screen 3-D Largely AbsentOne area in which you might think medium-and large-screen 3-D could work is digital signage for advertising. Of course, the 3-Dwould have to be autostereoscopic, that is,glasses-free. And for several years, largeautostereoscopic (AS) 3-D demonstration displays could be seen at Display Week andelsewhere. But there was no AS 3-D signageat the Digital Display Expo in late February
and very little at InfoComm in Orlando, whichfollowed Display Week by 3 weeks.
The Display Week exhibition did not devi-ate from this pattern. I saw only a modestnumber of large 3-D screens on the showfloor. Two of these were LG Display’s 55-in.AMOLEDs, in both the flat and curved ver-sions. Only the curved version was showing3-D content when I was at the booth, and bothversions used passive glasses.
Another 3-D example was from a more sur-prising source. Fraunhofer’s Heinrich Hertz
Institute (HHI) was showing a moderatelylarge (TV-sized) sample autostereoscopic dis-play with “viewpoint adaptation.” AlthoughAS 3-D displays often have several viewingzones for different angles of view, they are allbest viewed from a specific distance predeter-mined by the display’s design. HHI uses anAdobe After Effects plug-in suite to generatemultiple sets of views from the standardstereoscopic inputs. These multiview imagesare compatible with many existing AS 3-Ddisplays, according to HHI Research Associ-
Display Week 2013 Review: 3-DThe 3-D technology on the show floor this year was represented primarily by small, glasses-free displays with improved image quality.
by Ken Werner
Ken Werner is Principal of Nutmeg Consult-ants, specializing in the display industry, display manufacturing, display technology,and display applications. He serves as Directorof Marketing for Tannas Electronic Displaysand is a regular contributor to HDTVexpert. com and Insight Media’s Display Daily. He canbe reached at [email protected].
20 Information Display 5/130362-0972/5/2013-020$1.00 + .00 © SID 2013
3-D review
Fig. 1: The author’s finger points to imagery in Holografika’s HoloVizio light-field display. (Photo: Ken Werner.)
ID Werner p20-22_Layout 1 9/22/2013 2:18 PM Page 20
ate Bernd Duckstein. For the demo at DisplayWeek, there were three fixed viewing distances that Duckstein selected manually,but it is possible to automate the process bydetecting the viewer’s distance from the display.
Although the large 3-D displays at thisyear’s show were not the highlights, there wasan assortment of small–to–medium-sized AS3-D screens, some of which were interesting.
The most compelling 3-D display at Display Week was shown at the I-Zone, thearea designated for committee-reviewed table-top exhibits for prototypes and innovativedemonstrations. Space is free to the chosenexhibitors, thanks to the sponsorship of E Inkand the efforts of the volunteers on the selec-tion committee.
The device in question was the HoloVizioModel 80WLT light-field display made byHolografika Kft. in Budapest, Hungary (Fig. 1).
The display consisted of 80 projectionengines, each producing a 720p image,according to Holografika CTO Peter TamasKovacs, but the image on the exhibit floorappeared to have considerably less resolutionthan 720 lines. Kovacs said that may havebeen the result of misalignment produced byjostling in transit.
The display was driven by four GPUs con-tained in two computers that sat inside the display’s large pedestal and which were connected to the display with 20 dual-DVI
cables. Ideally, said Kovacs, each of the 80projection engines would show an independ-ently captured image, but a studio sessionwith 80 video cameras is clearly not realistic.So, the company uses four cameras and syn-thesizes the 80 separate views from them.
The result of this heavy-duty video process-ing is a 3-D display with a field of view of180° and continuous motion parallax that permits the viewer to “look behind” elementsof the image. The 3-D image is viewablefrom any position in front of the display; there
Information Display 5/13 21
Fig. 2: NLT’s autostereoscopic 7.2-in. 2-D/3-D prototype exhibited very low cross-talk thanksto its glass lenticular lens. (Photo: Ken Werner.)
(a) (b)
Fig. 3: Innolux 4.5-in. 2-D/3-D autostereoscopic display was able to show 3-D images in both (a) landscape and (b) portrait orientations.(Photo: Ken Werner.)
ID Werner p20-22_Layout 1 9/22/2013 2:18 PM Page 21
are no dead zones. The 80WLT is availablefor €60,000 by special order. Expect your unitto be shipped 3 months after it is ordered, saidKovacs.
Although the HoloVizio unit is undoubtedlyinteresting, you will not be seeing very manyof them given the price and production rate.So, it is perhaps fortunate that the bulk of the3-D displays on the exhibit floor were smallAS 3-D LCDs. Most were unsurprising, butleft–right crosstalk is improving on average,and some of the displays were based onnative-FHD (1920 × 1080) displays, whichdoes a lot for the image quality of the ASimage if the other engineering details aretaken care of properly.
Small AS 3-D Displays at the ShowNLT Technologies, formerly NEC LCD Tech-nologies, was demonstrating its multiview AS 3-D H×DP displays in which the horizontalsubpixel density is × times that of the verticalsubpixel density. In addition, each of the red,green, and blue subpixels is arranged in rowsinstead of the conventional columns. Thearrangement, an extension of the company’sHorizontally Double-Density Pixels (HDDP)arrangement, can display both 3-D and 2-Dimages simultaneously by simply changingthe input data. And, says NLT, it displays
“perfect 2-D images” without 3-D/2-Dswitching and delivers multiple views withoutreducing the display’s native resolution.
NLT showed a 7.2-in. HDDP 2-D/3-D prototype with viewing angles of 80/80 hori-zontally and 80/60 vertically, a contrast ratioof 600:1, and a luminance of 370 nits (Fig. 2).
In addition, the display incorporated glasslenticular lenses instead of polymer. Theresult, explained NLT’s Engineering ManagerBob Dunhouse, is less left–right cross-talkbecause glass is more dimensionally stableunder prolonged heating by the backlight thanis polymer. The claim was supported by aside-by-side comparison and an analysis thatshowed that the Qualified Binocular ViewingSpace (QBVS) of a display with the glass lensis twice that of conventional displays.
Innolux showed a 4.5-in. 2-D/3-D displaywith 1280 × 720 pixels in 2-D and 640 × 720in 3-D. Luminance in 2-D was 450 nits and225 nits in 3-D. The interesting thing aboutthe display was that it could show a 3-Dimage in both landscape [Fig. 3(a)] and portrait [Fig. 3(b)] modes simply by beingrotated 90°. The display used a 2-D/3-Dswitchable barrier.
Next on the Innolux counter was a similardisplay with eye tracking. The angular rangeover which the 3-D eye tracking operated was
rather limited, but an icon in the corner indi-cated when the image left the active range andhad automatically defaulted to 2-D.
Japan Display, Inc. (JDI) showed an auto-motive display in which an LC parallax barrier was switched by tracking the viewer’shead position, so the viewer’s (presumably thedriver’s) head was always in the display’ssweet spot. The display was 12.2 in. on thediagonal with a native 1920 × 720 pixels; the3-D resolution was 960 × 720 (Fig. 4).
Tianma Microelectronics showed a WVGAparallax-barrier 3-D module that produced350 nits in 2-D and 180 nits in 3-D with acontrast ratio of 800.
So, there was quite a bit of 3-D at DisplayWeek after all if you looked at the industrialpurveyors of smaller displays. And these purveyors are learning how to make displayswith less cross-talk and more forgiving 3-Dsweet spots. It is clear that eye tracking is theway to go for larger (but not large), single-user AS 3-D displays, but is it needed for ahand-held display in which the user can readily– even unconsciously – adjust the angle ofview with a slight rotation of his or her hand.?Consumers will make that decision for them-selves – if head-tracking AS 3-D displays getenough design wins to give consumers thechance. n
3-D review
22 Information Display 5/13
Fig. 4: JDI’s 12.2-in. autostereoscopic automotive display utilized head tracking to keep thedriver’s eyes in the display’s sweet spot. (Photo: Ken Werner.)
Display Week 2014SID International Symposium,
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June 1–6, 2014
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ID Werner p20-22_Layout 1 9/22/2013 2:18 PM Page 22
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Untitled-1 1 3/22/2013 11:27:13 PM
AMID the beautiful scenery of Vancouver,British Columbia, Canada, Display Week 2013offered a great deal to visitors looking for thelatest in OLED technology. Even before theexhibit opened, discussions about OLEDsand, in particular, OLED TVs were featuredduring the Business Conference on Mondayand also in the keynote speech given by Samsung Display President & CEO, Dr.Kinam Kim. In his talk, Kim described howSamsung sees the display market of the futurebeing dominated by OLEDs. He considers itthe key display technology for coming displaygenerations.
Dr. Kim also painted an enticing future ofadd-on features that OLEDs could enable fordisplays to come, ranging from the close-at-hand, such as transparency and flexibility, tothe more visionary, such as displays withembedded gas sensors or piezo-elements thatenable haptic feedback through the displaysurface.
Some of those visionary developmentswere on display on the exhibit floor in theform of demonstrators or products. TheFutaba Corp. booth probably had the mostinteresting and futuristic OLED demos. WhatFutaba was showing were a number of trans-parent and flexible models, including a flexi-ble OLED wristwatch with integrated touchfunctionality (Fig. 1). In addition to these
demos, Futaba also showed its first transparentOLED display product, which is used for theLenovo S800 smartphone.
Even though the displays at the Futababooth were based on a passive-matrixapproach, they all showed the potential ofOLEDs very nicely. Futaba appears to befocused mainly on automotive applications,which explains the company’s strong interestin flexibility. This aligned nicely with anobservation by Samsung’s Dr. Kim, whostated in his keynote speech: “There are noflat surfaces inside a car.”
Samsung emphasized its product portfolioof mobile devices at Display Week, showingnew versions of its OLED-based Galaxy S4smartphones. Among the technical aspects
that the company highlighted were the excel-lent color space and low energy consumptionof OLEDs. With regard to the latter, Samsungshowed OLEDs and LCDs in direct compari-son, claiming that 47% less energy is con-sumed by OLEDs in the so-called ALPM(AMOLED low-power mode). Even thoughthis power-consumption comparison couldconceivably be questioned by the LCD camp,the dynamic power consumption of OLEDs incontrast to the virtually constant consumptionof LCDs in all driving situations was veryapparent.
Samsung also showed its new pixel-arrangement scheme, which it calls the OLEDdiamond (Fig. 2). This new type of PenTiledisplay (with twice as many green pixels as
Display Week 2013 Review: OLEDsTVs were not the only OLED-based products of interest at Display Week.
by Sven Murano and Anke Lemke
Sven Murano joined Novaled in March 2004and is Vice-President, Product Management.He can be reached at [email protected]. After several years of experience in thesemiconductor industry, Anke Lemke joinedNovaled in January 2005 and is Marketing & Communications Manager.
24 Information Display 5/130362-0972/5/2013-024$1.00 + .00 © SID 2013
OLED technology review
Fig. 1: Futaba showed a futuristic watch with a curved OLED display.
ID Murano p24-27_Layout 1 9/22/2013 2:26 PM Page 24
red and blue ones) is supposed to deliver evenbetter image quality than the earlier striped-pixel PenTile display layout used in its GalaxyS3 model smartphone.
TV ProgressLG Display showed its 55-in. OLED TV set,which has been commercially available forquite some time on the Korean market. Inaddition, it also showcased a curved 55-in.AMOLED TV, which is now available for salein the U.S. as well as Korea (Fig. 3).
With those two items, LG Display certainlyhighlighted its commitment to OLED-TVtechnology. Until recently, it was the onlycompany with a commercially available large-screen OLED TV. (At press time, SamsungDisplay had just introduced a curved 55-in.OLED TV for sale in the U.S. as well asKorea.) LG Display also showed a 5-in. HDflexible OLED screen on a plastic foil sub-strate (Fig. 4). Besides the obvious freedomof being able to shape the display in waysbeyond the usual planar restrictions of glass,LG Display also emphasized the ruggednessof such panels.
Early visitors to the booth of LG Display atDisplay Week could try their luck with a ham-mer and a non-working dummy panel so as toexperience the shock resistance of the plasticdevice themselves. However, shortly after theopening of the show, the dummy panel myste-riously vanished from the booth.
A major topic at both the technical sympo-sium and business conference was the ques-tion of how OLED TV can be best produced.A common understanding throughout the talkswas that eventually printing processes couldbe a workable solution for structuring and fabricating OLED TVs. However, it was also understood that such processes still need at least a few more years of develop-ment in order to become mature enough formanufacturing.
Therefore, for the time being, vacuumevaporation of the OLED structures seems tobe the only feasible method of production.With regard to this technology, the principleline of debate spins around two very differentmethods of producing the color subpixelarray. On one side is the method favored byLG Display, which deposits a four-subpixelarray made up of a combination of fluores-cent-blue- and phosphorescent-yellow-emit-ting materials in a white-emitting OLEDstructure. (LG Display calls this “WOLED”
technology.) Each subpixel is then filteredwith red, green, blue, or white filters, makingup a four-subpixel matrix referred to as the“RGBW” approach.
Samsung Display meanwhile currentlyfavors an approach in which the red, green,and blue pixels are separate native color emit-ters without the need for any filter overlay.The displays made by this method have onlyRGB subpixels (no fourth white emitter);however, in the case of Samsung Displayimplementing the PenTile approach, there is ahigher ppi number for green than for R and B.These subpixels are fabricated by an evapora-tion step through a shadow mask, in which theRGB emitters are deposited through separateshadow masks next to each other. This structure is commonly referred to in theOLED community as an RGB side-by-sidearrangement.
One new player in this field entered the ringduring the symposium – the Taiwanese company AU Optronics Corp. (AUO) – whichreported results from a 65-in. AMOLED TV
that was also produced with shadow masks inan RGB arrangement. AUO did not, however,commit to production of devices with thatmethod during the conference.
The other big question that remains to beanswered is which backplane technology willserve the future AMOLED TV market best.Some presenters recommended oxide TFTs asa possible solution. The products by LG Display are based on this approach. On theother hand, Samsung Display stated that itprefers polycrystalline silicon at this time forits OLED-TV development. An idea of thecurrently running dispute over which technol-ogy is most effective could be obtained at the keynote sessions, in which Dr. Kim ofSamsung Display advocated the polysiliconapproach and John F. Wager of Oregon StateUniversity made a clear commitment to oxideTFTs as the most promising approach. A dis-cussion of the details of this debate would gobeyond the scope of this article, but it will bevery interesting to watch how this technologi-cal competition evolves.
Information Display 5/13 25
Fig. 2: Samsung demonstrated the brightness of an LCD (left) vs. an OLED (right) displayusing its new “OLED Diamond” pixel scheme.
ID Murano p24-27_Layout 1 9/22/2013 2:26 PM Page 25
In any case, AMOLED-TV developmentwill be strongly influenced by steadilyincreasing competition with LCDs, which aresetting new standards in terms of resolution
and color gamut. Clearly, it can be seen thatthe next generation of OLED-TV productswill have to answer the challenge of 4K × 2Kresolution and higher brightness, which
require improved backplanes, manufacturing,and OLED pixel technologies.
Microdisplays and LightingReturning to the exhibition floor, micro-displays based on the current wave of interestgenerated by Google glass were of note.Products and demonstrators of this technologycould be seen in the eMagin booth and also inthe I-Zone exhibit from SA Photonics, Inc.The news that Google glass will use an OLEDmicrodisplay produced by Samsung Displaywas announced on the last day of the exhibition.
Finally, a few words about OLED lighting.There were limited demos during the exhibi-tion at UDC’s and Novaled’s booth. Impres-sive improvements were, however, reported atthe symposium during the last sessions on Friday morning. Panasonic reported a newrecord, with a device achieving 114 lm/W inthe laboratory, using the company’s propri-etary light-outcoupling technology. Hitachidescribed progress in flexible lighting devicesmade from solution processing, and LG Chemreported on its 80-lm/W product, which willbe launched later this year. Also, in terms oflight extractions, some updates were given bythe glass-manufacturing companies AGC andSaint-Gobain, which both reported on light-scattering substrates for enhanced light out-coupling for OLED lighting. In practicalterms for comparing the efficiencies of LEDand CCFL lighting products to the aforemen-tioned OLED example, LEDs are passing the200-lm/W limit in the lab, and commercialproducts are at around 150 lm/W. CCFLs areat around 80–100 lm/W, with little room forimprovement.
Finally, it should be mentioned that forOLED electrode materials, several interestingcontributions have been made. Cambriosreported on its “Bottom-Emitting Large-AreaStacked White OLED with Silver NanowireNetwork as Transparent Anode,” whichdetailed the benefits of the company’sClearOhm silver nanowire material as analternative to ITO for OLED solid-state light-ing. ClearOhm transparent electrodes enableefficiencies of more than 40 lm/W, improveangle dependence of color, and can enablemetal-grid-free large-area OLED lightingtiles, such as the 100-cm² (10 cm × 10 cm)OLED tile that Cambrios created recently incollaboration with Novaled.
IBM showed some progress on makingOLEDs on graphene electrodes, reaching up
OLED technology review
26 Information Display 5/13
Fig. 3: LG Display showed curved OLED TVs at Display Week.
Fig. 4: LG Display showed a flexible OLED display on plastic foil substrate.
ID Murano p24-27_Layout 1 9/22/2013 2:26 PM Page 26
to 60% quantum efficiency for a greenOLEDs using a laboratory outcouplingregime. The American start-up companynVerPix presented some OLED pixels on carbon-nanotube electrodes.
If and when these new electrode materialswill be seen in OLED applications, such aslighting and display tiles, remains uncertain,but certainly the promises toward low costand flexibility are exciting.
In summary, Display Week 2013 showed anoverall positive momentum for OLEDs. Inparticular, the commitment of the two majorplayers from Korea to OLED TV is reassuringfor the industry. Even though several engi-neering problems still remain to be solved interms of OLED manufacturing and lifetime,there can be little doubt that, in the long run,OLEDs will develop into a major displaytechnology, especially with its promise fordevices with additional functionalities such astransparency and flexibility. n
Architects of World ClassDisplay EnhancementsEuropTec USA is a specialist in glass processing and fabrication for the display industry. As an expert in various nishing and processing technologies, we design and manufacture products for display applications.
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www.informationdisplay.org
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MANY OF US expect Display Weekto provide one of the best annual measures ofthe momentum and status of advances in display technology, and Display Week 2013lived up to that expectation yet again as a“can’t miss event.” The first measure of inter-est in reflective displays came at the e-Paperseminar I gave on the day before the sympo-sium and exhibit. The presentation was unfor-tunately the very last seminar of the day, in alarge room, and it was therefore pleasing tosee a sizable attendance for the second year ina row. Clearly, there is strong industry desireto understand what is available in e-Papertoday and what the future holds. Many of usworking in this area continue to field a bar-rage of inquiries for “zero-power,” sunlight-legible, super-lightweight, or flexible displays, all of which e-Paper is uniquelypositioned to satisfy. Our response tends tobe: “We are working on it, stay tuned!” Sothe demand for the next generation of e-Paperproducts remains robust, and the remainingquestion is what progress is being made to satisfy that demand.E Ink Corp. remains the dominant player in
the field, surrounded by a diverse set of tech-nologies and small companies vying to grabits market share through improved perform-ance or to enable new applications unmet by E Ink Corp’s electrophoretic imaging film.Unlike in recent years at the show, it was notthe insurgent technologies or companies thatcaused the greatest excitement in Vancouver;
it was E Ink Corp. itself. The big newsoccurred on Tuesday in the form of a newproduct line from E Ink Corp. that was notincremental and not an R&D demo that wouldnever turn into a product. The press release read: “E Ink Corp.
Launches Spectra, the World’s First TrueThree-Pigment Electronic-Paper Display.”This is significant for two reasons. First, itshows a major investment and advance towardcapturing market share in the electronic-shelflabel and signage market. The market rightnow is dominated by simple and dim reflec-tive liquid-crystal displays (LCDs), with atbest poor color that is relegated to only sub-sections of the display. Now, with E InkCorp.’s Spectra, any part of the display canprovide a deep black, a brighter and morepaper-like white, or a red color to highlightsales or promotions (Fig. 1).
The second reason for excitement steps usback to last year’s breakthrough reported byFuji-Xerox on full-color electrophoretic displays based on cyan/magenta/yellowswitchable particles. Many of us wonderedwhether more than two particles (black andwhite) could ever be commercialized. Theanswer is now yes, and it should be interestingto see just how far this type of technology cancontinue to advance for signage. Don’t expectit to lead to color eReaders anytime soon,though, because each time you add anothercolored particle, the switching speed slowsdramatically. The Spectra demos shown provided only 1-bit gray scale. Nonetheless,it is great to see a significantly new and visibly compelling product from E Ink Corp.Credit should be given also to the researchers formerly at SiPix Corp. (which was acquiredby AUO and then by E Ink Corp.) who origi-
Display Week 2013 Review: e-PaperA new product line from E Ink Corp. topped the surprises at this year’s show.
by Jason C. Heikenfeld
Jason C. Heikenfeld is a Professor in theDepartment of Electrical Engineering andComputing Systems at the University ofCincinnati. He can be reached at (513) 556-4763; [email protected].
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e-paper review
Fig. 1: E Ink Corp.’s Spectra, a new commercial product, adds a third color – red. At left is aschematic showing how the new product works. In the middle are examples of three-colorlabels that could be used as shelf labels in stores, and at right is a shot of a Spectra display alongside the author’s paper business card (conveniently in red, black, and white) for comparison.
E-Ink Spectra: How it works ... Example 3-color E-Ink Spectra Displays. With business card for reference.
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nally developed the technology that underpinsthis new E Ink Corp. product.The fluid in E Ink has a level of “sticki-
ness” to it, such that it takes a bit of a thresh-old of electric field to get colored particlesmoving such that more weakly charged parti-cles will move more slowly. The displays firstswitch between black and white colors, asnormal, and in the process move the red parti-cles to the back where they are invisible.Then, a weaker second electric field is appliedto move the red particles to the front in selectregions, and, voila, now you have color with-out the losses of side-by-side color-filter sys-tems such as RGBW (red, green, blue, andwhite). Simply put, the demonstrated units atthe E Ink Corp. booth looked great. How longthen until additional colored particles can beadded? Despite Fuji-Xerox’s 2012 demon-stration of full-color single pixels, the generalsuspicion is that full-color operation is stillfairly far away from commercialization. Other players showing e-Paper in the
exhibit hall included Sharp, Opalux, andQualcomm, each displaying familiar lookinge-Paper demonstrators. The Qualcomm boothhad two smartphones with the company’s“next generation” mirasol technology. Thesedisplays looked really, really good and com-pletely superior to the performance of thecommercially available Kobo eReader thatuses mirasol. If e-Paper modules like this canbe manufactured economically, it would betough for any other technology to competewith its visual performance in bright ambientlight. However, the prototypes were, in fact,static images, meant to convey the expectedperformance of a “multiposition” mirror thatuses optical interference to generate any purecolor within a single subpixel (except white,which still significantly limits the maximumpossible white state). These static-image prototypes are just thin-film interferencestacks, and I recall seeing similarly beautifulstatic images shown a decade ago by Iridigm(acquired by Qualcomm in 2004). Given themanufacturing challenges Qualcomm hadfaced for just the two-position mirrors, multi-position mirrors are likely to raise even moredifficult challenges (Fig. 2). Also in the exhibit was the Japan Display,
Inc. (JDI), reflective-display prototype, whichI was able to see up close for the first time.The color looks excellent for a reflective LCD(Fig. 3). It employs a gain reflector. I wasvery skeptical of gain reflectors until recently,
when through some of my own company’s(Gamma Dynamics) developments I saw that,if properly implemented, gain reflectors canlook diffuse over a wide viewing cone and indiffuse or off-axis lighting. This is the case,however, only if the reflector is properly engineered and has adequate amplitude. Gainreflectors, when they work best, leverage thefact that for a personal device such as aneReader, you can orient the panel towardyourself. This allows the reflector to then doat least one of two things: (1) reduce light loss
due to total-internal reflection (TIR) at thefront glass and (2) amplify the light fallingwithin the typical viewing cone of the user. In the case of the color reflective LCD from
JDI, the designers chose to use a highly direc-tional (and conventional) gain reflector thatdoes not make efficient use of off-axis (diffuse) illumination. This was evident ifyou blocked the directional light source abovethe demo and permitted only diffusion illumi-nation. So this embodiment would require abright ambient light source located just behind
Information Display 5/13 29
With business card for reference. With directional lighting at booth. With diffuse (off-angle) lighting only.
Fig. 2: Wouldn’t it be great if e-Paper displays looked like this? This “static” non-switchabledemonstrator from Qualcomm shows the excellent potential performance of a multi-positionmirror, next to a white business card for brightness comparison.
Fig. 3: At left, the JDI color reflective LCD appears next to a business card for color reference.The middle image shows the LCD with directional lighting at the booth, and the image at rightappears with the author’s portfolio blocking the light so the panel receives off-angle light only.
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your head or shoulders to make a compellingeReader or tablet display. However, such dis-plays could be valuable in a fixed orientationand lighting environment, which, for example,signage or electronic shelf labels can provide.Also to its credit, in its proceedings paper, JDI does show diagrams and openly communicates the lighting and measurement orientationsused in its characterization of performance. The e-Paper symposium talks were all on
Tuesday this year, with a few other relatedpapers and posters scattered throughout theremainder of the week. In the first talk of theday, Seiko-Epson reported on a binary (1-bit,only black/white) eReader based on E Ink thatallowed fast scrolling, page turning, and peninput. I tried the pen input at the author-interview session and it was nearly flawlesswith seemingly immediate response. The talkshowed how high resolution (300 ppi) canhelp spatially dither gray-scale images withfast 1-bit E-Ink switching. Most importantly,the talk provided human-perception tests thatshow that simple black/white operation mightbe better for dedicated reading and office documents – applications for which the fasterpage turning, scrolling, and pen-input mightbring real value to the user. It has beenknown for some time that E Ink can providefast switching if you are willing to give upsome or all gray scale, and, for video demos,sacrifice display contrast.
During the second e-Paper session, myPh.D. student Matthew Hagedon delivered aninvited talk on “Progress in ElectrofluidicImaging Film.” The data presented supportsan argument that this is the only known tech-nology with a roadmap that can provide highresolution, video speed, and SNAP (newsprint)quality color. Unfortunately, as I am inti-mately aware, the technology development isearly stage, only about 18 months old, andactive-matrix-driven modules are just now indevelopment. One promising demonstrationfor the electrofluidic imaging film, though,was basic proof of concept for passive-matrixaddressing. Passive-matrix addressing ishighly desirable for applications such as signage and electronic shelf labels, where lowcost is critical. Passive-matrix addressing is something that E Ink currently cannot provide. In the second e-Paper session, IRX Innova-
tions (Henzen et al.) presented some muchmore sophisticated active-matrix-driven electro-osmotic display technology (Fig. 4).This approach is unique in terms of particlemovement, but not enough information waspresented to provide a deep understanding ofthe underlying physics. The early prototyperesults were modest (3:1 contrast, slowswitching of several seconds) but the teamfrom IRX maintains that the upside potentialincludes a maximum white state near 70% in
stacked CMY (cyan, magenta, yellow) opera-tion and near-video speeds. The electro-osmotic approach is novel in many ways andwill be worth following closely as IRX con-tinues to develop the technology. Another talk of note was given by Norihisa
Kobayashi from Chiba University. Prof.Kobayashi was part of the early electro-chromic material development that led toRicoh’s recent demonstration of a strikinglybeautiful color active-matrix electrochromicdisplay. This year, he presented a single electrochromic cell that could switch betweena clear state, a black state, and also a mirrorreflector state. Although this is early-stagework, and the maximum number of switchingcycles is unknown, I can imagine many inter-esting applications ranging from switchablemirrors, to privacy windows, to light- andthermal-management technology. The last note of interest came not at Display
Week 2013, but right before the conference,with the revelation that Amazon had just pur-chased Liquavista from Samsung. The historyof this company began with Philips, fromwhich it was spun off in 2006. Then it waspurchased by Samsung, then Amazon. Timewill tell what this all means. It has been clearfor some time, especially with its investmentin Lab 126, that Amazon takes the hardwareside of displays quite seriously. The specula-tion is, of course, that this could lead to anext-generation color-video reflective eReader or tablet product from Amazon. With Display Week 2013 now behind us,
progress clearly continues on all fronts. With-out doubt, e-Paper is a real and growing segment of the display industry. What is lessclear is how much longer it will take to satisfyconsumer and corporate demands for the nextgeneration of e-Paper technology. OLEDsand LCDs will continue to battle it out incoming years, but neither will supplant manyof the e-Paper applications. With the hugeshift to LCD tablets already enacted, e-Paperis left to control much of its future destiny andthat will depend on its ability to provide brightwhites, more saturated color, and access tobroader media content such as seamless webbrowsing and at least crude animation/video.Looking forward to 2014! n
e-paper review
30 Information Display 5/13
Fig. 4: Alex Henzen of IRX Innovations displays active-matrix magenta and yellow modulesbuilt on electro-osmotic technology.
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IN the first article of this series, we talkedabout the fundamental building blocks of anew technology venture: inventions andteams. It is a fact that this talent generallywants to be paid. Almost all technology ventures need significant capital to grow theiroperations.1 Unless the founders can con-tribute significant personal cash, something Iwould not recommend even if possible, thatmoney needs to come from external investors.
In this article, we will talk about the differentsources of investment, their requirements, andtypical valuations and terms.
Capital NeedsThe first step is to identify the capital needs ofyour venture. Few technology businessesachieve profitability after a single round offinancing, so it is worth planning multipleinvestment rounds. The time horizon betweenrounds thus becomes the determinant of thecapital needs of the business. Each round willideally be raised at a higher valuation than thelast one – failure to do so will make your earlier investors very unhappy, with oftenpainful consequences for your ownership ofthe business. Thus, the goal is to raise enoughmoney to achieve a material increase in valua-tion and then have sufficient time left to raisethe new round. For convenience, investment rounds are
often given names such as Seed Round, SeriesA, Series B, Series C, etc. The labels have nofirm meaning and are sequential (e.g., SeriesB is the second round raised after a Series A).That said, common understanding in theindustry defines typical rounds as follows:Seed Round (usually below $500K): The
initial team is in place with a business plan,but things are usually still a bit rough aroundthe edges. The capital will likely be used tocomplete the core of the business and buildthe first product prototypes. Revenue is gen-erally not expected.Series A ($1 million - $3 million): Usually
this is the first major and/or institutionalround. The business is fully operational with
possible initial revenue. Certainly, some formof market validation should be in place, aswell as all the core team roles filled with high-quality people.Series B ($3 million +): At this stage, the
engine of the business is humming and thenew capital just adds more fuel. The focuswill be on scaling and growth management.Of course, there are plenty of companies thatraise a Series B, i.e., their second institutionalround, while still looking like the Series Acompany described above, but that’s generallya sign of something having gone wrong orboth rounds being smaller than usual2 (seeFig. 1).Most early-stage companies will consider
either a Seed Round or maybe an early SeriesA if they are able to bootstrap through theSeed stage without raising significant externalcapital (possibly with the help of the three“Fs” – Friends, Family, and Fools. When determining capital requirements,
consider how much money the business needsto go from one stage to the next. So, if youare raising a Seed Round, consider how longit will take to achieve product revenue and fullteam build-out (the general criteria for Series
Raising Capital for Technology VenturesInvestors come in different packages. It’s important to know the various types, along withtheir pluses and minuses. This article is the second of four in a series by a venture capitalexpert who has both launched and funded new companies.
by Helge Seetzen
Helge Seetzen is CEO of TandemLaunchTechnologies, a Quebec-based company thatcommercializes early-stage technologies fromuniversities for its partners at major consumerelectronic brands. He also co-founded Sunnybrook Technologies and later BrightSideTechnologies to commercialize display tech-nologies developed at the University of BritishColumbia. He has published over 20 articlesand holds 30 patents with an additional 30pending U.S. applications. He has a Ph.D. ininterdisciplinary imaging technology (physicsand computer science) from the University ofBritish Columbia.
Information Display 5/13 310362-0972/5/2013-031$1.00 + .00 © SID 2013
venture capital series
1Exceptions are usually limited to service businesses that can generate immediate revenue. This is rarefor genuine technology ventures where the product,the technology, still requires significant develop-ment before it can be commercialized. In this con-text, it is also important to remember that ventureimplies growth. Businesses that essentially out-source the work of the principals as consulting orcontract work might be able to self-finance from thestart, but are best described as self-employment and not ventures. Venture capital investors will certainly not be interested in such opportunities, even if theyprovide very nice lifestyle returns for the principals.
2BrightSide Technologies, Inc., my second venture,was an example of the latter. For business reasons,we raised the first five rounds of angel financingbelow $1 million each. At that point, we were tech-nically raising a Series F, but in practical terms wehad raised less than $4 million total and were thusfunctionally similar to a Series A company. Valua-tion rose with each of our rounds, and the final out-come was a success for all investors, so the aboveguidelines are not definitive by any means.
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A). Then, add at least 30% as a buffer sincenothing ever works as planned in a startup.Finally, add 6 months of additional operatingtime to account for the fact that fundraisingitself takes time. The total amount neededover this period defines the capital require-ment for your new round. With that numberin hand, you can consider the different fund-ing sources available to early stage technologyventures.
Sources of FundingWe currently live in a fortunate time for entre-preneurs – investment capital is readily avail-able. However, times do change, apparentlyfairly cyclically, so enjoy these years whilethey last.3 But money comes from many dif-ferent sources. In practice, however, the widevariety of investor types can be grouped intothree principal sources of funding:Accelerators: These entities tend to pro-
vide much of their value in kind, throughmentorship, support, and services, but oftenalso invest relatively small amounts of moneyinto the business (usually tens of thousands ofdollars but rarely more). With a few excep-tions, accelerators are designed for venturesthat require assistance to get off the groundwith the money being usually a secondarybenefit – so evaluate them based on the valueof the offered support in relation to your venture’s weaknesses. Angel Investors: Angel investors are high
net-worth individuals willing to invest inearly-stage companies. Many of them are former entrepreneurs who are keen on experi-encing the start-up rollercoaster but, ideally,without putting their nose all the way to thegrindstone again. They tend to invest rela-tively modest amounts, with $25K–250Kbeing a common range per investor. Fortu-nately, angels tend to work in groups, often informally organized networks, so it is usuallypossible to raise combined rounds of angelcapital up to about $1.5 million. Venture Capital: Professional investors,
called Venture Capitalists (VCs), manage significant funds on behalf of their limitedpartner (e.g., pension funds, government
funding, large corporations, etc.). Such fundscome in different sizes and shapes, but com-monly invest upward of $500K during initialrounds. Unlike angels, venture capitalists alsohave the ability to follow their initial invest-ment with major secondary and tertiaryinvestment rounds, reaching often into thetens of millions of dollars.These are the three most common types of
investors for early-stage technology ventures.4Of course, the world is full of variance,including the more recently emerged conceptof super angels – effectively venture capitalistswho manage smaller funds and behave morelike angel investors. Nevertheless, it is easiestto think of investors in these three broad cate-gories: those that assist, those that invest theirown money, and those that invest other people’smoney. These distinctions make a major difference in terms of the amount of availablecapital and the goals of the investors.Angel investors are generally more com-
fortable with modest returns but usually alsowant to see some cash coming back to them ina shorter time frame than VCs. A commonrule of thumb is that a 2–3× return in 3–4years will make most angels happy. Venturecapital funds can deploy much more capital
over longer fund cycles of 10–12 years, butalso have much more aggressive 5–10× returngoals due to their non-linear compensationstructure (more on this next month). Individ-ual investment goals of course vary greatly, soI would strongly recommend an open discus-sion before you seal your new relationship. In general, it is a good idea to build a positiverelationship with future investors long beforeyou need their money – date first, then marry.Often the match-up between capital needs
and sources of funding is fairly obvious at thispoint. Service business or other opportunitieswith limited capital requirements are oftenbetter served by angel investors. On the otherhand, if your business plan requires $10 million+to build a viable product or advanced demo,then venture capital is likely the only way togo. Maybe you can find an accelerator with
good access to deep-pocket VC funds or somewell-connected angels, but your road willeventually lead you through the doors of aVC. Once on this road, make sure to optimizeyour business strategy around the goals andtimelines of venture capital. Display hardwareprojects are commonly on this trajectory, withall the positive and negative implications.Of course, reality is rarely this conveniently
defined, so all kinds of mixed deals are possi-ble. Some ventures are able to combineangels and seed VC investors; some use astrong group of angel investors to drum upsupport for a high-valuation VC round, and soforth. But such schemes are usually best left
venture capital series
32 Information Display 5/13
Fig. 1: The valuation history of BrightSide Technologies (one of the author’s ventures) is shownover a period of 5 years.
3Those who feel that fundraising today is too diffi-cult should talk to veterans of earlier times. Forexample, Sunnybrook Technologies. Inc., my firstventure, started fundraising in 2001 – hardly a timewhen IT technology start-ups were popular, giventhe recent demise of nearly the entire sector in the dot-com bubble.
4Non-investment sources of funding of course alsoexist: grants, loans, subsidies, etc. Most of thoseare often inaccessible for early-stage ventures,though I would encourage all entrepreneurs to atleast canvass the available economic developmentgrants in their jurisdiction – free money is always ablessing for any new venture.
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to seasoned entrepreneurs – managing differ-ent interests is a difficult game with generousamounts of pain waiting on the sidelines ifyou get off track.
Valuation and TermsOnce you have defined your investmentsources and have built a good relationshipwith them, there comes the magic momentwhen you receive a term sheet. As the nameimplies, this is a short document listing theprincipal terms of the investment deal. Thatdocument will have two important numbers:the size of the investment and the valuation ofyour company. Let’s ignore the more com-plex terms for now and focus on the mostbasic scenario to explain the terminology: ifyou are raising $1 million and your companyis deemed to be worth $3 million, then your“pre-money valuation” is said to be $3 millionand your “post-money valuation” will be $4million. Post-money, you will of course onlyown 75% of your company ($3 million out of$4 million) so you will have experienced a25% “dilution.”Post-money valuation is just pre-money
plus cash raised, but how is the pre-moneyvaluation determined? At this point the tech-nical reader will likely expect a complex formula but reality is much less fancy (at leastuntil you reach the earnings-based valuationmodels of late-stage ventures). Counter-intuitively, your early-stage valuation is lessabout the value elements of your business andmore about the type of investor you canattract. Most investors will take 20–40% ofyour company for each round of financingregardless of the amount invested. Thus, aVC Series A round of $2 million tends to havepre-money valuations of $3 million – $5 million,while an angel seed round of $500K will havepre-money valuations of about $1 million –$2 million. There are, of course, plenty ofexceptions, but as a rule of thumb this tends tohold fairly well for early stage rounds.So, why use an approach that is so unscien-
tific? It’s about time and mind-share. Thestake for investors needs to be small enoughto leave incentive for the management teamand large enough to make their mind-shareinvestment worthwhile. For example, mostVC funds are expected to have one of theirpartners sit on the Board of Directors of eachof their investments. Since a partner can onlyreasonably sit on about five boards, they needto make large enough investments to makeeach deal worth their time. Thus, whatchanges during early stage rounds is theamount of money you get for a given fundinground of 20–40% dilution – hot companiesgetting more while weaker ones get less. The goal then is to rapidly advance your
venture to the point where it can raise moneyfrom investors with deeper pockets, watchingyour effectively pre-money valuation rise as aside effect.5 Do not spend on infrastructure,support hires, or anything else that does notcontribute to the advance to the next investorclass. Of course, the value elements of yourventure – team, product, revenue – are themeans by which you advance to a newinvestor class. So, ultimately it is all stillabout building team and traction.So far, in this series, we have covered
building a great founding team and, with thisarticle, the basics of capitalizing that team. Inthe next piece, we will dig a bit deeper intothe structure of a venture capital (or angel)financing scenario, including common dealterms, pitfalls, and some tips for valuationoptimization. n
venture capital series
Information Display 5/13 33
5One of the most common business failures comesfrom a lack of understanding of advancement crite-ria. A growing company might be capped to an ~$4million valuation range simply because its localangel group cannot find more than $1 million incapital and cannot close the deal if its members getless than 20% of the company per round. If theCEO cannot advance to the next investor group, thecompany is likely doomed no matter its businesssuccess.
J O I N S I DWe invite you to join SID to participate in shaping the future development of:
• Display technologies and display-related products
• Materials and components for displays and display applications
• Manufacturing processes and equipment
• New markets and applications
In every specialty you will find SIDmembers as leading contributors totheir profession.
http://www.sid.org/Membership.aspx
Display Week 2014SID International Symposium,
Seminar & ExhibitionSan Diego Convention CenterSan Diego, California, USA
June 1–6, 2014
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Jenny DonelanInformation Display Magazine411 Lafayette Street, Suite 201
New York, NY 10003Fax: 212.460.5460
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industry newswww.informationdisplay.org
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OLED-BASED DISPLAYS are well-established for use in smartphones and tablets.OLED TVs are still in the early stages but willenter higher volume markets soon. In thelighting field, however, OLEDs are still exotic.
To reach a larger lighting market segment,OLEDs have to compete against traditionallighting solutions and, additionally, fulfilllighting requirements for dedicated applica-tions. To achieve this, synergies between displays and lighting architectures must beaccomplished.
In 2011, the world residential lighting market was around €21 billion, which repre-sents approximately 40% of the general light-ing market.1 This number covers new fixtureinstallations, including the full value chain,lighting-system control components, andlight-source replacements. The professionalmarket segment is €34 billion in total, whichis the other 60% of the market. Additionally,the value per application in the professionalmarket is higher than in the residential market; these factors make the professionalmarket rather attractive for OLED applications(Fig. 1).
Application RequirementsTo date, OLED lighting solutions exist mainly
in art installations and decorative lighting.These niche applications are tolerant of highcosts and low performance. Actual OLEDapplications in high-end decorative luminairesor art installations are possible because therequirements for luminous flux or lightingperformance are low. To enter a wider rangeof professional lighting applications, OLEDsmust improve in technical parameters and incost. Additionally, innovative integration con-cepts for large lighting areas are necessary.
Professional lighting describes the marketsegment for B2B (business-to-business) solutions, covering office, shop, hospitality,industrial, architectural, and outdoor lighting
solutions. These application fields have manyindividual application requirements, but, ingeneral, the applications can be summarizedas shown in Table 1.
OLEDs could in a near-to-middle timeframe cover only a part of these applications,based on their parameter field, which can besummarized as follows:
Medium-to-low luminous flux due tolimited brightness level.
Medium areas due to actual fabricationlimitation.
High lighting quality based on a goodlighting mixture (CRI > 80–90).
Medium-to-high cost aspect. Very good design aspect based on slim
format and homogenous lighting area.Based on these criteria, the application
fields of hospitality, shop, and office are thebest candidates for OLED applications in thenear future.
Office-related solutions are the largest market segment in general lighting; in 2011,they represented €8 billion worldwide.1 Thismarket segment is very suitable for OLED-related lighting solutions because the applica-tions are indoor, higher-cost related (especiallyin Europe), and require high-quality lightinggeneration.
Unfortunately, the largest applicationsinside the office market are downlights andrecessed luminaires. Both applications are notreally suitable for OLED integration. Down-lights require very high brightness levels andluminous flux; recessed luminaires are mainly
OLEDs for Professional Lighting ApplicationsOrganic light-emitting diodes (OLEDs) already represent a strong market segment in display applications such as mobile devices. In the lighting market, they are still in the beginning phase. To achieve a relevant market segment, OLED technology has to compete in terms of performance, cost, and other unique features against established light-source technologies.
by Jörg Amelung, Christian Kirchhof, Tino Göhler, and Michael Eritt
Jörg Amelung, Christian Kirchhof, TinoGöhler, and Michael Eritt are with TridonicDresden GmbH & Co. KG in Dresden, Germany. Jörg Amelung can be reached at [email protected].
34 Information Display 5/130362-0972/5/2013-034$1.00 + .00 © SID 2013
frontline technology
Fig. 1: The cost/volume ratio for differentlighting applications shows that costs are highand volumes are low in the niche areas of artinstallations and decorative lighting.
Residential
Professional
Decorative
Art
high
high
low Cost level
Volu
me
low
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cost driven and do not need a slim form factorbecause in ceilings additional installationssuch as air conditioning are required.
Based on the limited luminous flux ofOLEDs, potential applications for OLEDlighting currently involve those that are inclose proximity to the user. The most interest-ing applications are desk, wall-integrated,pendant, and free-standing luminaires (Fig. 2).
There are two ways of implementing newlighting technology for such applications: byretrofitting elements or by designing newluminaires. Retrofit solutions would requireOLED elements that replace in size and lumi-nous flux traditional fluorescent tubes such asT5, T8, or T-CL. Such retrofit solutions withLEDs have already entered the marketplace.
Information Display 5/13 35
Table 1: Requirements are compared for various professional applications.
Office Shop Hospitality Industrial Architectural Outdoor
Main type of Area, Slot, Slot, Spot, Area, Slot Area, Slot, Area, Spot Spot,light Spot, Downlight Spot, Downlight Downlight
Downlight Downlight
Luminous flux, Medium High Medium High Low HighBrightness
Area Medium Medium Medium High High High
Lighting quality High High High Low Medium Low
Cost segment Medium Low Medium Low Low Very low[$/lm]
Design aspect High Medium Medium Low Medium Low
Fig. 2: The following office-lighting applications are the most likely to be commercially viable for OLED at this time: wall luminaires (top left),pendant luminaires (top right), light lines or slot lighting (bottom left), and free-standing luminaires (bottom right).
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They are ideal because there is no need toredesign the luminaire, which saves cost andtime.
For OLEDs, these kinds of retrofit solutionswill not work because of the form factors andbrightness levels of traditional fluorescentsolutions. New flat luminaire designs are thebest way to integrate OLEDs into applica-tions. In Table 2, the relationship betweenvolume, price, and type of luminaire is shown.OLED applications will be implemented firstinto design-oriented luminaires and will follow the route to mass volume by reducingcost and improving performance.
The requirements in price and performancefor OLEDs rise dramatically for functional and mass-volume luminaires because there OLEDs will be in direct competition with LED solutions.
Even for this first stage of application, thedesign-oriented luminaires, OLEDs will haveto fulfill some requirements that are commonlyrestricted by the applications.
These requirements are: Luminous flux > 9000 lm/m² (> 3000
cd/m² if assuming lambertian emission). Color-temperature standards; 3000 and
4000K. Area sizes: 0.3 × 0.3 m or 0.6 × 0.6 m. Simple integration.None of the OLEDs now in the marketplace
fulfil these requirements; in most cases, theluminous emittance is too low or the colortemperature is lower than 3000K and/or thesizes are too small.
One additional important target is the costaspect. Actual OLED solutions are about 100times more expensive than LED-based ones,so OLED process costs have to be dramati-cally reduced. OLED display fabrication iswell-positioned in the market, so there is thequestion of which synergies could be usedbetween the display and lighting segment toimprove performance and reduce fabricationcosts.
With regard to OLED TVs, some of themain parameters are close to those of OLEDlighting, so both industries use similarapproaches. Normally, the display architec-ture for the two is completely different basedon the required RGB pixel arrangement. Nevertheless, there is an alternative colorarrangement in some displays that use whitewith color filters, which offers certain advan-tages, especially for large-area displays.2 Inprinciple, this arrangement consists of a largeOLED lighting area integrated into an active-
matrix backplane. The fabrication synergiesare maximal in that arrangement, so similarmachine concepts could be used. The OLEDstacks in such color-by-white arrangementsare also similar; nevertheless, the white colorpoint and brightness level are different. Thus,OLED displays and lighting fabrication tech-nologies could enjoy synergies in the case offabrication technologies and OLED stackarchitecture. This could make the marketentrance for OLED lighting easier, especiallyin the professional sector.
Highly Efficient OLED ModulesOLED modules represent an important steptoward achieving large-area lighting solutionswith accepted and required lumen packages.OLED glass panels are not very easy to inte-grate. The thin-film electrodes on glass haveto be contacted in a good manner to avoidvoltage drops to the module. Additionally, theglass itself cannot be handled easily, and anadditional optical out-coupling system has to
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Table 2: The relationship betweenapplication and price/volume is
proportional.
Fig. 3: This OLED module system measures99 × 99 mm per panel.
Fig. 4: Module efficacy is plotted vs. average luminance of the module.
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be integrated. Based on the limited sizes of OLEDs (up to 15 × 15 cm²), large areas ofOLED lighting have to be subdivided in several OLED lighting plates.
OLED lighting modules represent an import intermediate level for integration. Such modules could be easily mounted to coverlarge lighting areas via a mechanical supportsystem. Important aspects of these OLEDmodules could be subdivided as follows:
Small contact areas to maximize theOLED lighting area.
High-luminous-intensity homogeneity. Minimal thickness. Robust contact system.To achieve a robust contact system, the
OLED electrode contacts are bound by a flex-ible contact spring to a PCB connection plate,which results in a total contact resistance of < 1 W for a 99 × 99-mm OLED module.
A potential OLED module system is shownin Fig. 3. The module combines a large activearea (> 80% lighting area) with a slim formfactor (< 3 mm thickness) and a robust contactsystem for use in large-area applications.
Based on very efficient OLED panels (fabricated by LG Chem), the OLED modulesystem allows very efficient OLED lighting. The modules achieve a luminous efficacy of over 50 lm/W at 3000 cd/m² (averaged luminance at 230 mA) and a total luminous flux of over 100 lm for a 350-mA current, which results in a lumi-nous emittance of over 12,000 lm/m² (Fig. 4).
Mirror OLED Module SolutionsBesides performance, it is important to pro-vide new features or form factors to users toearn new application scenarios. One interest-ing implementation for OLED modules insideprofessional applications is the off-state mirror surface. There are two solutions toachieve an off-state mirror. In the first, theout-coupling foil on top of the OLED is notapplied; in the other, an additional mirror isused as secondary optics on top of the light-emitting surface.
An optical system with an additional mirrorplate achieves a highly efficient mirror-likeOLED in the off-state. In the on-state, theoptimized mirror allows a stable color coordi-nate at different angles, with only a low shiftof color compared to an OLED with no out-coupling or secondary optic system. Theappearance is uniform even at the edges of theOLED module.
This solution also allows for a more effi-cient OLED module; the OLED efficacy isstill 34 lm/W at a luminous flux of 59 lm (99 mm x 99 mm) based on an OLED panelwith initially 40 lm/W and a milky diffuse surface (Fig. 5).
An innovative luminaire solution based onsuch modules has been demonstrated by thecompanies Selux and Art+Com. The lumi-naire Manta Rhei is a pendant type with indi-vidual dimming of 140 mirror-type OLEDmodules and kinetic movement of the OLEDpanels that is enabled by the bending of themounting metal sheet. Based on individualdimming, the illuminance level remains con-stant during movement (Fig. 6).
The Future of OLED LightingTo achieve a larger market segment, OLED’sbest near-time possibility is in fulfilling prod-uct requirements for professional lighting solutions. High brightness and efficient OLED solutions could be achieved by optimizedmodule solutions. Novel surface finishingssuch as a high-quality off-state mirror surfaceallow for new luminaire appearances, whichmay accelerate the OLED market penetration,although initially toward the high end. Last, synergies between OLED solutions in displays and lighting could generate advantages interms of fabrication costs and OLED stacks.Such advantages could boost both industries.
AcknowledgmentSome of these OLED results were achievedinside the BMBF-funded OLED project SO-LIGHT (FKZ 13N10536).
References1Lighting the way: Perspectives on the globallighting market, 2nd ed. (McKinsey & Com-pany, Inc., August 2012).2C-W. Han et. al., “55-inch FHD OLED TVEmploying New Tandem WOLEDs,” SIDSymposium Digest of Tech Papers 43, Issue 1,279–281 (June 2012). n
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Fig. 5: Module efficacy is shown vs. drivingcurrent of the mirror-type OLED module.
Fig. 6: The Manta Rhei luminaire by Seluxand ART+COM consists of 140 mirror-type modules. (Source: Selux.)
Display Week 2014SID International Symposium,
Seminar & ExhibitionSan Diego Convention CenterSan Diego, California, USA
June 1–6, 2014
SAVE THE DATE
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LIGHTING represents almost 20% ofglobal electricity consumption. A savingspotential of more than 1000 TWh (terawatthours) per year by 2030 is possible if conven-tional inefficient lamps are replaced by highlyefficient solid-state lighting (SSL).1,2 Thetotal electricity consumption of the world wasapproximately 18,000 TWh in 2010, accord-ing to Japan’s Agency of Natural Resourcesand Energy (www.enecho.meti.go.jp/english/).Light-emitting diodes (LEDs) are a well-known source of highly efficient solid-statelighting (SSL), and LED equipment has grad-ually been replacing conventional lightingsuch as that based on incandescent bulbs.Organic light-emitting diodes (OLEDs) areanother candidate for next-generation SSLbecause they are compact, lightweight, highlyresponsive, and highly flexible in terms ofdesign. Commericalized OLEDs have alreadyexceeded the efficiency of incandescent bulbs.However, they have not yet surpassed LEDs.The efficiency of OLEDs is mainly deter-
mined by three factors: internal quantum efficiency (IQE), electrical efficiency (EE),and light-extraction efficiency (LEE). First,
optimization of the carrier balance withenergy levels and the mobility of stacked lay-ers for emission, transportation, injection, orblockage is required to maximize IQE, espe-cially for effective radiative hole–electronrecombination. According to spin statistics,the hole–electron recombination yields singletand triplet excitons by a ratio of 1:3, respec-tively. It is well known that phosphorescentOLEDs enable radiation from triplets and thatits IQE has already reached nearly 100%.3,4
EE is inversely proportional to the drivingvoltage, which is controlled by charge injec-tion and carrier transfer. High-mobility mate-rials or electrical doping techniques haveenabled an extremely low driving voltage ofOLED devices that has come close to theoreti-cal limits.5 However, restrictions are requiredto achieve both low driving voltage and a longlifetime because of the fundamental issue ofdurability in organic materials. These archi-tectures can also suffer from resistive losses
High-Performance White-OLED Devices forNext-Generation Solid-State Lighting The efficacy of white OLEDs has reached 100 lm/W with RGB-phosphorescent emitters andlight-extraction technologies. OLEDs have therefore already exceeded the efficacy of typicallighting equipment with fluorescent lamps.
by Kazuyuki Yamae, Hiroya Tsuji, Varutt Kittichungchit, Nobuhiro Ide,and Takuya Komoda
Kazuyuki Yamae, Hiroya Tsuji, Varutt Kittichungchit, Nobuhiro Ide, and TakuyaKomoda are with Eco Solutions Company,Panasonic Corp., Japan. K. Yamae can be contacted at [email protected].
38 Information Display 5/130362-0972/5/2013-038$1.00 + .00 © SID 2013
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Fig. 1: A standard light-extraction model for OLED shows total internal reflection (TIR) at twointerfaces.
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induced by the relatively large currentsrequired by low driving voltages.
The largest potential of the aforementionedthree factors is in LEE. Only about 20% ofthe total generated light can escape to the airfrom conventional OLED devices, due to totalinternal reflection (TIR) at the interfaces asshown in Fig. 1 and explained by Snell’s lawas one of the limiting factors in LEE. Sinceorganic layers and glass substrates havehigher refractive indices than air, light thatreaches the outer boundaries of the device atwide incident angles encounters total internalreflection (TIR) and is trapped inside thedevice instead of being able to escape. Thereflected light is then absorbed back into theorganic layers or electrodes.
Various optical structures with micro-sizedtexture or nano-sized gratings fabricated onthe surface of the substrate are simple meth-ods that can be used to improve LEE.6 How-
ever, these technologies are not able to extractthe remaining light confined in the transparentelectrode and organic layers – this trappedlight is called the waveguide mode.
Some internal light out-coupling structures such as scattering layers or diffraction gratings fabricated in the organic layers have been use-ful in reducing the waveguide mode and haveachieved better LEE.7-9 However, those scat-tering layers or gratings usually have roughsurfaces, which reduce reliability through cur-rent leakage or short circuits. A special highrefractive index (n ~ 1.8) substrate withmicro-patterned texture has achieved excellentLEE because of the improved transmissionfrom thin layers to the substrate.10 However,reliable high-refractive- index glass (n ~ 1.8)at low cost is not commercially available forlarge-area substrates applicable to OLEDs.
In this article, we focus on the progress oflight-extraction technology using a Built-up
Light Extraction Substrate (BLES)11,12 – atechnology developed by Panasonic engineer-ing. Using this BLES, an efficacy of over 100 lm/W was achieved in combination withdeveloped white-phosphorescent OLEDdevices. This measure of 100 lm/W is widelyrecognized as the first destination for next-generation lighting because the efficacyexceeds current typical lighting applicationsusing fluorescent lamps.
Built-Up Light-extraction Substrate(BLES)A cross section of a BLES structure with abottom-emitting OLED is shown in Fig. 2.BLES comprises a transparent electrode, ahigh-refractive-index (n = 1.77 at 550 nm)micro-lens-array (MLA) structure made frompolyethylene naphthalate (PEN) film, and aglass substrate for encapsulation. An air gap exists between the MLA and the glass substrate.
The BLES was fabricated as follows: Atransparent electrode was previously depositedon one surface of PEN film. MLA was fabri-cated onto the opposite side of the film. Thisfilm was then laminated to a glass substratewith the MLA side facing the glass. Themicro-patterned texture of the MLA wasattached to the glass substrate, and the air gapnaturally occurred between the textures andthe glass. This assembly was then vacuum-dried at 80°C for at least 15 minutes in orderto remove the residual water and gases beforeuse. After the deposition of the OLED deviceonto the film on the top side, electrodes on thefilm were connected to the bus electrodes onthe glass substrate with a conductive paste.The film and deposited organic device werecompletely encapsulated by a cavity glass.
Due to the high-refractive-index structure,light emitted from the organic layers propa-gates into the PEN and MLA layers withoutTIR. Owing to the existence of the air gapbetween the out-coupling texture and glasssubstrate, extracted light from the MLA wasable to transmit into the glass substrate with-out TIR, and an excellent LEE was expected.
BLES has other merits in addition to theenhancement of light-extraction efficiency.First, the smooth surface of the film is appli-cable to a large-area OLED device. Second, the rigid protection from water vapor, reactivegases, or other physical damages by the glass substrate enables better durability of the OLED device on the film and micro-textures. Plus, thesubstrate is appropriate for commercial use
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Fig. 2: This cross section of an OLED shows the structure of the built-up light-extraction substrate (BLES).
ID Yamae p38-43_Layout 1 9/22/2013 2:50 PM Page 39
because each component is relatively inexpen-sive compared to high-refractive-index glass.
Optical Design for BLES The propagating light in BLES is divided intotransmitted diffraction and reflected diffrac-tion at the interface of the MLA and the airgap. Transmitted diffraction is extracted fromthe air without TIR at the glass surfaces asdescribed previously. Reflected diffraction isextracted through the multiple reflections inOLED and BLES, or absorbed. Thus, BLEShas the potential to realize excellent LEEwhile suppressing internal absorption sinceTIR is almost eliminated. In a conventionalstructure, the waveguide, substrate, and airmodes are 50%, 30%, and 20%, respectively.
If we use a high-refractive-index substratesuch as PEN, the waveguide mode is trans-ferred to the substrate mode and the substrateand air modes are 80% and 20%, respectively.BLES enables substrate mode to air mode. Ifwe can achieve a no-absorption device, 100%of light is extracted. On the other hand, a conventional structure can achieve only 50%,since the waveguide mode is retained inorganic layers and cannot be extractedwhether absorption is high or low.
The influence of internal absorption to LEEin BLES was fully investigated to obtainhigher LEE. To begin with, the transparencyof BLES was examined. The measurementresults of reflectance and transmittance ofBLES are shown in Fig. 3. To avoid the noise
caused by scattering, the MLA was replacedby a flat layer with an equivalent thickness ofits height (about 5 µm) as shown in Fig. 3.No absorption was observed in BLES sincethe summation of reflectance and transmit-tance was almost 100% in the region of a visible wavelength. Spectral ripples by opti-cal interference were not observed as refrac-tive indices of PEN film and high-n materialfor MLA was similar.
On the premise that no-absorption channelis in the BLES, the diffraction at MLA andinternal absorption in the OLED became theprimary focus of investigation. In this study,the LEE of the OLED with a high-refractive-index extraction layer was simulated by a calculation model combined with rigorouscoupled wave analysis (RCWA) and ray-tracing.13 The calculated model is shown inFig. 4. Model A was almost equivalent to BLES, which was composed of a high-refractive-index substrate (n = 1.78) and MLA(n = 1.78). The glass substrate under theMLA was removed to simplify the calculationbecause its absorption and influence on LEEdid not need to be taken into consideration inthis case. Model B was a conventional light-extraction structure composed of typicalexternal out-coupling MLA film (n = 1.52)that had the same texture as Model A with aglass substrate (n = 1.52).
The simulation algorithm is described as follows. First, the incident light I1(θi,φi) can be calculated by using a Fresnel coefficient in theOLED multilayers. θi and φi are the incidentand azimuthal angles, respectively. The aver-age value of p and s polarizations is applied tosimplify the calculation. The total radiationfor the first incidence is expressed by
(1)
The integral numbers of m,n are diffractionorders of the x and y directions. Tm,n(θi,φi) is the transmittance for (m,n) calculated byusing RCWA. On the other hand, the reflec-tion for each direction at the first incidencecan be given by a function of the reflectionangles (θr,φr) as
Rm,n(θr,φr) is the reflectance for (m,n) calcu-lated by using RCWA. Vm,n is a rewrite of sinθi as a function of θr,φr, and |Jr,m,n| is the
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Fig. 3: Reflectance and transmittance measurements for BLES.
Fig. 4: Two different optical simulation models (A and B) were used for BLES.
(2)
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Jacobian determinant ς(θr,φr)/ς(θr,φr). The second incidence is obtained from the reflectance Ro(θr,φr), which is calculated by using the Fresnel coefficient matrix for the OLED multi-layers and ξ1(θr,φr), which is calculated byusing Eq. (2). θr,φr are regarded as the secondincident angles because the incident angle of light is not converted at the reflective electrode:
I2(θr,φr) = Ro(θr,φr)ξ1(θr,φr) (3)
Therefore, the radiation for the second inci-dence η2 is determined by substituting Eq. (3) into Eq. (1). The radiation of eachincidence for the multiple reflection of lightcan be determined in the same mannerbecause its angle is not converted in theOLED and electrodes. Consequently, theextraction efficiency η is described as the sumof all radiation from the micro-structure:
(4)
The calculated result is shown in Fig. 5. It is indicated that the influence of internalabsorption was more dominant in Model Awith its high-refractive-index substrate than in Model B with its low-refractive-index substrate. The high-refractive-index substrateremoved the waveguide mode, which wasconfined within the organic layers. Thus, all light from the emitting layer could pass throughthe optical pass with multiple reflections as described. Therefore, the LEE was more strongly influenced by the internal absorption in the OLED with a higher-refractive-index substrate.
Then, the high-absorption layers were carefully specified and replaced by lower-absorption materials. A comparison of light-extraction structures (BLES and conventionaloutcoupling film) with different absorptiondevices is shown in Fig. 6. The opticalenhancement of the external quantum effi-ciency (EQE), which is in proportion to LEE,was obviously improved with lower absorp-tion. The trend was more dominant in theBLES than with the the conventional structurewith external out-coupling film.
Performance of the Two-UnitPhosphorescent White OLEDThe improvement of EE was also studied dueto the different driving voltages amongdevices and because the theoretical energygap was still large. Typically, the blue-phosphorescent host that enables high quan-
tum efficiency has poor injection and trans-port properties.14,15 Thus, we assumed thatthe blue-phosphorescent emitting layer wasthe main component of high voltage. In thisstudy, the interfacial injection barrier betweenthe electron-transport layer and the blue-phosphorescent emissive layer was examined.Various electron-transport materials with
different energy levels were investigated, andthe driving voltage was reduced without beinga crucial issue to the quantum efficiency andlifetime. Meanwhile, the injection of holesinto the blue-phosphorescent emissive layerwas also investigated. The use of the carrier-balancing design resulted in a successfuldecrease in driving voltage.
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Fig. 5: The optical simulation result of LEE for both Models A and B.
Fig. 6: Optical enhancement with lower absorption was better for BLES than for conventionalout-coupling film.
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The authors developed two-unit all-phosphorescent white-OLED devices thatwere optimized for maximized IQE and life-time, minimized driving voltage, and propercolor coordinates. The low-absorption materi-als, specific light-distribution design, andvoltage-reduction technologies as previouslymentioned were also applied. The perform-ance of fabricated devices with 1-cm2 pixels isshown in Table 1. The luminance dependenceon efficacy at Device A is shown in Fig. 7.Device A showed an extremely high efficacyof 114 lm/W and a quite long half-decay life-time of over 100,000 hours. It also showed125 lm/W at 100 cd/m2 and 102 lm/W at 3000cd/m2. Over 100 lm/W was maintained up toa high luminance of about 4000 cd/m2. LEEwas dramatically improved due to the low-absorption materials and specific distributionpattern with BLES. This indicated that almosthalf of the light was extracted from the emit-ting layer because an EQE of about 100% wasachieved in the two-unit device. The EE wasalso improved, and the voltage was reducedby about 0.6 V compared to that of Device C.
Next, a large-area OLED device based onDevice A was fabricated. The emission areawas 25 cm2. The uniform emission withoutdark spots and visible defects was realized, asshown in Fig. 8. The properties of this panelare shown in Fig. 9. A quite high efficacy of110 lm/W and a long lifetime of 100,000hours at 1000 cd/m2 were also obtained forthis OLED panel. The efficacy of the paneldecreased by about 3% from the pixel (1 cm2)
because the voltage of the panel slightlyincreased with a voltage drop in the circuit orthermal influence. Color coordinates were inthe region of the white color.
Future Prospects for OLED LightingFigure 10 shows the current-efficacyprospects for OLED lighting. The authors’immediate target in terms of efficacy is 130 lm/W by the end of this year (2013), a target set by the New Energy and Industrial
Development Organization (NEDO) atwww.nedo.go.jp/english/.
The arrival of an over 100-lm/W OLEDlighting device would be a turning point forentering the general lighting market. It is necessary to develop a light-extraction tech-nology for the waveguide mode such as BLES for the realization of an over 100-lm/W OLED lighting panel. Particular effort should befocused on issues such as reliability, produc-tivity, and cost competitiveness in order forOLED lighting to reach the marketplace forsignage, decorative illumination, office andindustrial use, and indoor and outdoor light-ing. Those development activities are alsonow ongoing in parallel.
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Table 1: The performance of fabricated all-phosphorescent OLED devices A, B, and C (1-cm2 pixel) is compared.
All phosphorescent white OLED Device A Device B Device C
Low absorption materials optimized installed installed
Specific distribution pattern optimized installed —
Lower voltage technologies optimized installed —
Luminance 1,000 cd/m2 1,000 cd/m2 1,000 cd/m2
Efficacy 114 lm/W 101 lm/W 87 lm/W
External quantum efficiency 99% 84% 81%(estimated LEE) (>49%) (>42%) (>41%)
Driving voltage 5.5 V 5.9 V 6.1 V
Estimated lifetime (LT50) >100,000 h >30,000 h >100,000 h
CRI 80 86 82
Color coordinates (0.48, 0.43) (0.44, 0.44) (0.46, 0.42)
Color temperatures 2,550 K 3,200 K 2,800 K
Fig. 7: Luminance depends on efficacy (shown for Device A from Table 1).Fig. 8: A large OLED panel (25 cm2) wasfabricated based on Device A.
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AcknowledgmentsThis work was supported by NEDO as “Fundamental Technology Development ofNext Generation Lighting of High-efficiencyand High-Quality” project started in March2010. We also thank Idemitsu Kosan Co.,Ltd., as a member of the project, and also Universal Display Corp. and Nippon Steel &Sumkin Chemical Co., Ltd., for their kindprovisions of high-performance materials.
References1“25 Energy Efficiency Policy Recommenda-tions,” International Energy Agency (2011).2“Monthly Electricity Statistics,” InternationalEnergy Agency (2013).3C. Adachi, M. A. Baldo, M. E. Thompson, and S. R. Forrest, “Nearly 100 % internal phospho-rescence efficiency in an organic light-emit-ting device,” J. Appl. Phys. 90, 5048 (2001).4M. A. Baldo, D. F. O’Brien, Y. You, A. Shoustikov, S. Sibley, M. E. Thompson,and S. R. Forrest, “Highly efficient phospho-rescent emission from organic electrolumines-cent devices,” Nature 395, 151 (1998).5R. Meerheim, K. Walzer, G. He, M. Pfeiffer,and K. Leo, “Highly efficient organic lightemitting diodes (OLED) for displays andlighting,” Proc. SPIE 6192, 61920P/1 (2006).6T. Komoda, H. Tsuji, N. Ito, T. Nishimori,and N. Ide, “High-Quality White OLEDs andResource Saving Fabrication Processes forLighting Application,” SID Symposium DigestTech. Papers, 993 (2010).7Y. Sun and S. R. Forrest, “Enhanced lightout-coupling of organic light-emitting devicesusing embedded low-index grids,” NaturePhotonics 2, 483 (2008).8J.-H. Jang, M.-C. Oh, T.-H. Yoon, and J. C. Kim, “Polymer grating imbeddedorganic light emitting diodes with improvedout-coupling efficiency,” Appl. Phys. Lett. 97,123302 (2010).9B.Riedel, J. Hauss, U. Geyer, J. Guetlein, U. Lemmer, and M. Gerken, ”Enhancing out-coupling efficiency of indium-tin-oxide-freeorganic light-emitting-diodes via nanostruc-tured high index layers,” Appl. Phys. Lett. 96,243302 (2010).10S. Reineke, F. Lindner, G. Schwartz, N. Seidler, K. Walzer, B. Lüssem, and K. Leo,“White organic light-emitting diodes with fluorescent tube efficiency,” Nature 459, 234(2009).11T. Komoda, K. Yamae, V. Kittichungchit, H.Tsuji, and N. Ide, “Extremely High Perform-
ance White OLEDs for Lighting,” SID Symposium Digest Tech. Papers, 610 (2012).12K. Yamae, H. Tsuji, V. Kittichungchit, Y. Matsuhisa, S. Hayashi, N. Ide, and T. Komoda, “High-Efficiency OLEDs withBuilt-up Outcoupling Substrate,” SID Sympo-sium Digest Tech. Papers, 694 (2012).13H. Kikuta, S. Hino, and A. Maruyama,“Estimation method for the light extractionefficiency of light-emitting elements with arigorous grating diffraction theory,” J. Opt.Soc. Am. A. 23, 1207 (2006). 14N. Chopra, J. Lee, Y. Zheng, S-H Eom, J. Xue, and F. So, “High efficiency blue
phosphorescent organic light-emittingdevice,” Appl. Phys. Lett. 93, 143307 (2008).15N. Seidler, S. Reineke, K. Walzer, B. Lussem, A. Tomkeviciene, J. V. Grazulevi-cius, and K. Leo, “Influence of the hole block-ing layer on blue phosphorescent organiclight-emitting devices using 3,6-di(9-car-bazolyl)-9-(2-ethylhexyl)carbazole as hostmaterial,” Appl. Phys. Lett. 96, 093304(2010).16“Solid-State Lighting Research and Devel-opment Multi-Year Program Plan,” U.S.Department of Energy (2013). n
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Fig. 9: The performance of the fabricated OLED panel (25 cm2).
Fig. 10: Current-efficacy prospects for OLED lighting based on the outlook of luminaire efficiency from Ref. 16.
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MOST people think about solid-statelighting in terms of white light – for streetlights, vehicle headlights, or subway-stationlighting. Of course, we do not live in a blackand white world, and our colorful world couldbenefit from illumination by longer wave-length light-emitting diodes (LEDs). In fact,scientists have pursued this line of researchfor five decades, as depicted in Fig. 1. Whilethe first LEDs were fairly simple pn-junctiondevices, they were quite complicated for theirtime. Today’s chips are more sophisticated, asa result of several difficulties scientists had toovercome during development.
First, the conversion efficiency was fairlypoor due to the low quality of the crystals themselves. Impurities and lattice defects made the conversion of electrical energy in light(photons) inefficient. Then, most of the lightgot absorbed again before it left the LED die.Absorption took place most of the time in thelayers themselves, more severely in the sub-strate and also at the metal contacts. Andwhile the first LEDs were made from InGaAlP(indium gallium aluminum phosphide) andAlGaAs (aluminum gallium arsenide) in therange between orange and infrared, today’sLEDs use additional materials and reach into the UV range of the light spectrum. Packagingconcepts and designs also matured dramatically, in parallel with the LED dies. While the firstLED devices were only slighty brighter than aglowing candle, LED systems now are brightenough for headlamps in cars and even trains.
Today, many applications require yellow,red, or hyper-red illumination. Such applica-
tions include projectors, color mixing forwarm white illumination, hyper-red illumina-tion coupled with blue light for greenhouses(as shown in Fig. 2), and also infrared illumi-nation with high brightness for closed-circuitTV, adaptive cruise control for cars, or lightcurtains (door detectors) in elevators.
After more than 12 years of efforts in thin-film technology, Osram Opto Semiconductorsrecently achieved a significant technologicalbreakthrough: a red LED at 200 lm/W at adominant wavelength of about 615 nm. Forred light, 200 lm/W is quite challenging, asthe theoretical limit for 615 nm with 100%efficiency is about 300 lm/W. So, 200 lm/Wis coming fairly close.
Currently, two companies claim to havesurpassed 200 lm/W – both in a laboratorysetting at specific current densities. To placethese developments in context, the balance ofthis article briefly recounts the history of colored-LED development.
How LED Lighting WorksIn solid-state lighting devices, the light is generated in the semiconductor crystal. Here,the electrical energy is converted into pho-tons, and, in this crystal, Osram introducedimprovements to make the entire system moreefficient. To get the light out of a light pack-age, the barrier of total internal reflection(TIR) at the crystal–die boundaries has to be
New Milestones for LED LightingThin-film technology has enabled a new generation of high-brightness LEDs.
by Martin Behringer
Martin Behringer is with Siemens HL andOsram Opto Semiconductors. He can bereached at [email protected].
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q
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Fig. 1: Brightness development for red, yellow, green, and blue LEDs is shown for the last 50years.1
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overcome. As the light is reflected back intothe die, it is incident to the surface of the diewith an angle larger than a specific value.There are two ways to help emit the light.The first is to continuously change the angleof the light so if it is reflected once; the direc-tion will be changed and it can escape in thenext run. Changing the direction of the lightcan be done by surface roughening or byinternal absorption and re-emission. Theother way is to reduce the loss mechanism(equal to absorption without re-emission oflight with the same wavelength) as far as pos-sible. This gives the light more opportunitiesto leave the die before it is lost.
Colored light can be generated eitherdirectly (by generating the desired colorthrough direct emission) or by conversionfrom one emission spectrum to another. In thefirst case, typically, a medium is excited elec-trically and emits photons in a specific wave-length. In the second scenario, a photon isemitted, then that photon is absorbed in amedium, and then another photon of a second,longer wavelength is emitted.
LEDs made from InGaAlP can directly andefficiently generate light for the wavelengthrange from 560 nm to about 660 nm.
The internal efficiency of a metal organicvapor-phase epitaxy (MOVPE) LED makes itthe most commonly used crystal growth tech-nology in the LED industry today. Efficiency
has increased to more than 90% in the longerwavelength range. But due to the high index
of refraction of InGaAlP LEDs, only 4% ofthe generated light can leave the chip directlyto be used for illumination; the remaining96% is either reabsorbed by the material orreflected at the chip/air interface and eventu-ally absorbed into the chip. Encapsulation insilicon or resin reduces the disadvantage ofinternal reflection. But, as in InGaAlP, it hasa very high index of refraction of about 3.4and because there is no encapsulant thatcomes close to this value, light out-couplingremains a problem.
The Development of Thin-filmTechnologyThin-film technology was invented by thelighting industry to increase efficiency andreduce light loss. (Many companies workedon this technology, and many now offer thin-film devices, but Osram was one of the first tocommercialize it, winning a German FuturePrize for its technological efforts.) In thin-film LEDs, the light is also generated in aquantum-well structure. In contrast to con-ventional LEDs, the growth substrate isremoved and the active epilayers are bondedonto a carrier, which can be germanium, silicon, or another material that matches therequirements for this carrier. A highly reflect-ing mirror can be deposited in between theepilayer and the carrier, which prevents thelight from being absorbed in the substrate. In
Information Display 5/13 45
Fig. 2: LEDs are now employed for a widevariety of applications, from solid-state light-ing to projectors to industrial applications.Here, multiple monochromatic LEDs are combined in a horticultural lighting system.
(a) (b)
Fig. 3: A schematic sketch of a conventional LED is shown on an absorbing substrate (a) next to a thin-film LED with a metal mirror between theactive epilayer and carrier (b).
ID Behringer p44-48_Layout 1 9/22/2013 3:04 PM Page 45
addition, the active epilayers can be so thinthat the light is absorbed differently frombefore, when thick layers were required toextract light efficiently. Normally, the surfaceis roughened to enhance light extraction ormicroprisms are included to increase effi-ciency (see Fig. 3).
In Figs. 3(a) and 3(b), the blue line showsthat the current is directed away from thebond pad to avoid shadowing. The red arrowsdepict the light path. The light, which is initially emitted toward the substrate, isreflected by the underlying mirror and redirected toward the chip surface where itcan then leave the semiconductor die.
Figure 4 highlights the historic efficiency of red LEDs (dominant wavelength, 615 nm).As the triangles and diamonds demonstrate,conventional LEDs reached a peak efficiencyof approximately 30 lm/W.
Beginning in 1998, Siemens/Osram beganresearch to develop thin-film LEDs for high-brightness emission. Initially, a number ofdifficulties arose. Perhaps the biggest prob-lem was transferring the thin semiconductorlayer (~ 5 µm, which is about 1/10 of thethickness of a human hair) to a carrier in alarge area (5 µm / 100 mm = an aspect ratio of20,000). Because this layer is very fragile andrequires a high yield for an economicallymeaningful concept, about 10 years transpiredbetween the first publication of the idea in1993 and Osram’s first commercial ThinFilmLED in 2003. Regardless of this and otherthin film problems, it quickly became obviousthat by using thin-film technology, higherbrightness can be obtained (see the trianglesin Fig. 4). By 2010, levels of approximately140 lm/W were reached.
Some advantages of thin-film LEDsinclude:
Scalability: In theory, all chip sizes canbe made similarly, and, in turn, possesssimilar characteristics and performance,according to their size.
Surface emitters have Lambertian beampatterns, and thus make it possible tocombine many chips side by side withoutchanging the beam pattern. Also, a Lambertian beam pattern means that theLED seems to have the same brightnessfrom all viewing angles, and a chip withthis profile is suitable for both reflectorand focusing optics.
High efficiency.
Cost-efficient design and manufacturingprocesses (based on lm/$).
During the last few years, further investi-gations into loss mechanisms within thedevices have not only improved efficiency,but also reduced cost and increased reliability.An analysis of different materials and semi-conductor compositions used within the diodefor electrical conductivity and optical trans-mission helped in the replacement of absorb-ing layers with non-absorbing layers ofsimilar or even better functionality.
Figure 5 depicts the current curve and efficiency for a 1-mm² die mounted into a laboratory package, optimized for efficientout-coupling of its generated light.
In Fig. 5(a), the light output for currents upto 350 mA is shown. A linear curve indicatesefficient light generation over a wide currentrange. In Fig. 5(b), the efficiencies are given.
The orange curve depicts the efficacy inlm/W, while the black curve provides wall-plug efficiency.
Both curves show a distinct maximum atabout 50 mA, with approximately 201 lm/Wand 61%, respectively. At 350 mA, the valuesreduce to 168 lm/W and 52%. The explana-tion for this decline can be found in the redcurve, which shows the external quantum efficiency. It shows a very broad maximum,and the value is almost unchanged between 50and 350 mA and between 58% and 59%. Thedecline in efficacy and wall-plug efficiencymust therefore be attributed to an increase inoperating voltage due to still-existing ohmicresistances within the die. The high lm/Wvalues were reached with a red die, whichemits at a dominant wavelength of about 609 nm at room temperature. For longerwavelengths, eye sensitivity lessens and,therefore, similarly high lm/W values areharder to realize. On the other hand, high
frontline technology
46 Information Display 5/13
Fig. 4: The historic efficiency of red LED brightness is shown by black diamonds indicatingvolume emitters on an absorbing GaAs (gallium arsenide) substrate. Red points indicate thin-film LEDs since 1999.
ID Behringer p44-48_Layout 1 9/22/2013 3:04 PM Page 46
wall-plug efficiency values are easier to real-ize with longer wavelengths. Therefore, thehigh value of 61% is quite remarkable.
These improvements were made possible inthe following ways:
By reducing the absorption of the layersas much as feasible, it is possible toextract more light, even if it travels 10times through the die before escaping thesemiconductor.
This was accomplished, in part, byincreasing the bandgap and, in part, byadjusting the doping. To avoid high-ohmic resistances at these high operatingvoltages, increasing thickness improvedthe conductivity of the layers. The con-tact design was optimized to keep theoperating voltage low. Figure 6 shows a1-mm² die. The dense arrangement ofthese metals’ current paths enables strongelectrical performance despite adjusteddoping levels.
Finally, these improvements resulted in avery-broad process window, which allows forhigh yield and, therefore, lower overall cost.
This new technology was applied to chipsizes of varying lengths: 250 µm, 300 µm,500 µm, 750 µm, and 1 mm. A 150 µm and a2-mm² die followed in 2012. The dominantwavelength range is from 590 to 645 nm; 560nm and infrared range followed in 2012 and2013, respectively.
As mentioned above, maximum efficacy isreached at about 610 nm, while wall-plug efficiency is highest at a wavelength of 645 nm.
Figure 7 depicts the characteristics for a 1-mm² die at a dominant wavelength of 645 nm (l = 660 nm peak) in the same laboratorypackage as used for the 615-nm emitting chip.The output power over current and the wall-plug efficiency are shown.
The output power rises linearly with currentand reaches about 437 mW at 350 mA (atabout 2.1 V). The wall-plug efficiencyreaches about 59% at 350 mA and is above70% between 5 and 60 mA. Due to reducedeye sensitivity (photopic curve), the maximumoutput at 350 mA is only 21 lm. Lifetimedepends on operating conditions such as current and temperature. The entire LEDcommunity is continuously working toimprove the reliability of these devices.
With the new generation of thin-film dies,however, output power could be increased by30–50% for a bare die compared to the previ-
ous generation and about 10–30% for a pack-aged die in an LED. This is quite significant.With this kind of increase, new and morenumerous applications can be addressed. Analready widespread application is the combi-
nation of highly efficient – but aestheticallyunpleasant – cold white with amber or red,which changes the color temperature to amore visually pleasant and high-quality white.As a result, both higher overall efficiency
Information Display 5/13 47
Fig. 5: (a) The light-current curve and (b) the efficiency/efficacy over the current of a 1-mm²LED in a laboratory package .
(a)
(b)
ID Behringer p44-48_Layout 1 9/22/2013 3:04 PM Page 47
and good color rendering can be achievedsimultaneously.
Meanwhile, projection and signaling appli-cations absolutely require high-efficiency redlight and will doubtlessly profit from thesebreakthroughs. As far as mobile applicationsare concerned, either more power or longerbattery life will provide tremendous customerbenefits. For industrial applications, lowerenergy consumption will reduce operatingcosts and brighter devices will minimize initial installation expenses.
In this context, it is clear that improvement in 660-nm LEDs will also have a positive impact
on LED-illuminated greenhouses. With suchhigh efficiency, energy costs can be reducedby almost half compared with conventionallighting; furthermore, LED cooling is madeeasier. For example, when comparing a lightwith 40% efficiency to the above-mentionedrecord values, it is realistically possible togenerate 75% more light with the sameamount of electrical energy and up to 250%more light at the same amount of waste heat.
Due to the improved performance of thechips themselves, package and luminairedesigners are emboldened to design biggerand higher-powered packages and lamps thatare driven at higher operating currents. Whilethe first LEDs were for the mA range, todayoften several amperes are run through the die.Even though efficiency has been greatlyimproved, these higher operating conditionsstill require good thermal management, due tohigher total load. Thus, modern LEDs andluminaires must provide low-ohmic resistancein terms of electrical supply; they must effi-ciently remove the heat with low-temperatureincrease, and they must also guarantee effi-cient light out-coupling and beam shaping tofulfil needs for modern light sources.
What Comes Next? Considering 60% efficiency, it is clear thatincremental brightness improvements will beharder to realize as we approach the ideal of100%. With that said, other parameters con-
tinue to require improvement. In particular,companies will want to see better productionand process values.
Also important will be improvements inhigh-current and high-temperature operation.Certain devices are commonly characterizedat room temperature, while approximately 80–100°C is a more realistic operating condi-tion. Therefore, work is being done to opti-mize output power at these temperatures, aswell as reducing the shift in operating para-meters when changing the temperature.
Last but not least, light out-couplingremains a constantly evolving challenge. Onthe package level as well as on the bare die,there is ongoing research dedicated to obtain-ing every photon that is generated out of thedie. Certainly, out-coupling in bare die con-figurations offers a wide range of possibleimprovements.
To summarize, since 1998, thin film hasbecome a preferred solution for generatinghigh-brightness LEDs. It was recently deter-mined how to reduce optical and electricalloss mechanisms to realize a maximum effi-cacy output of 200 lm/W. This enables far-broader LED use in many applications, whichwill increase lighting quality considerably.
References1Source: Elsevier/Academic Press. Thisimage was published in M. George Craford,“High Brightness Light Emitting Diodes,Semiconductors and Semimetals,” Overviewof Device Issues in High Brightness LightEmitting Diodes (Elsevier/Academic Press,1997), p. 48. n
frontline technology
48 Information Display 5/13
Fig. 6: Shown is the illumination pattern of a1-mm² die from the latest thin-film generation.
Fig. 7: Light output and wall-plug efficiency are demonstrated over the operating current for a1-mm² die emitting at 660-nm peak.
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DISPLAY ON-LINEFor daily displayindustry news
www.informationdisplay.org
ID Behringer p44-48_Layout 1 9/22/2013 3:04 PM Page 48
Display Week 2014 Symposiumto Feature OLED TV, WearableDisplays, 3D, and Lighting
The Society for Information Display hasissued a call for papers to be presented at the2014 Display Week Symposium. SID’sannual Display Week is the premier event for the global display industry. This year’ssymposium will feature presentations onevery aspect of display technology, but submissions on the following special topicsare particularly encouraged: OLED TV,Wearable Displays, 3D, and Lighting. Thisyear’s event takes place June 1–6, 2014, inSan Diego.
For the OLED-TV special topic, submis-sions on all advanced OLED-TV technologiesare encouraged, including novel device struc-tures, backplane technologies, manufacturingprocesses, deposition techniques, mask fabri-
cation, encapsulation, driving methods, andnext-generation applications.
The special topic on Wearable Displays will cover the emerging development of wearable display products, applications, and technologies. This is one of the fastest growing areas in both consumer products and technological develop-ment. Paper topics include wearable applica-tions, near-to-eye systems, textile displays,and more.
The 3D symposium sessions will encom-pass display technologies for enabling depthperception in viewers, applications for 3D displays, 3D content generation, measurementand characterization of 3D systems, andhuman factors.
Last but not least, the special topic onLighting will focus on advances in the LEDand OLED industries. Submissions on allaspects of solid-state lighting are encouraged,including novel lighting systems, lightingmeasurement, backlighting, optical systems,and more.
Work in the new fields listed above mayalso relate to the following general sympo-sium topics: Active-Matrix Displays, AppliedVision/Human Factors, Display Applications,Display Electronics, Display Manufacturing,Display Measurements, Display Systems,Emissive Displays, e-Paper and Flexible Displays, Liquid-Crystal and Other Non-Emissive Displays, OLEDs, Projection, andTouch and Interactivity.
The Society for Information Displayencourages the submission of original paperson all aspects of the research, engineering,application, evaluation, and utilization of displays. Paper submissions are welcomed for any of the general symposium or specifictopical sessions.
For information about submitting an abstract(due Dec 2, 2013), see “First Call for Papers”on www.sid.org.
— Jenny Donelan
Information Display 5/13 49
NEWSSOCIETY FORINFORMATION
DISPLAY
J O I N S I DWe invite you to join SID to participate in shaping the future development of:
• Display technologies and display-related products
• Materials and components for displays and display applications
• Manufacturing processes and equipment
• New markets and applications
In every specialty you will find SIDmembers as leading contributors totheir profession.
http://www.sid.org/Membership.aspx
Display Week 2014SID International Symposium, Seminar & Exhibition
June 1–6, 2014San Diego Convention CenterSan Diego, California, USA
www.displayweek.org
ID SID News Issue5 p49_Layout 1 9/22/2013 3:13 PM Page 49
The biggest piece missing in the puzzle sofar is the commitment to larger investments inmanufacturing volume. This is similar to thesituation that AMOLED display makers werein some years ago before Samsung led theway.In contrast to AMOLED displays, however,
production lines for lighting modules are farless complex and cost intensive. So we willnot have a limited amount of companies dom-inating the market, but rather a multitude ofcompanies as active producers. With a 40%annual reduction expectation, OLED lightingprices should reach a level where functionalrather than decorative uses will become viable– probably in the next 2–3 years. Now mightbe the right time to invest in those missingadditional manufacturing lines…. n
Sven Murano is Vice President of ProductManagement for Novaled AG in Dresden,Germany. He can be reached at [email protected].
continued from page 4
50 Information Display 5/13
guest editorial
continued from page 3
industry news
Display Week 2014SID International Symposium, Seminar & Exhibition
June 1–6, 2014San Diego Convention CenterSan Diego, California, USA
www.displayweek.org
Shanghai AVIC and NLT FormNew CompanyIf you’ve been wondering when the folksinvolved in Renesas/NEC/NLT/Tianma wouldchange company names again, wonder nolonger: Shanghai AVIC Optoelectronics Co.,Ltd., and NLT Technologies, Ltd., haveannounced the official launch (currentlyscheduled for November 1, 2013) of a newjoint venture, Tianma NLT America, Inc. Thenew company has been created to provideAMLCD solutions specifically for the Ameri-cas industrial market. It will have responsibil-ity for sales, marketing, and engineeringsupport of the NLT/Tianma product line aswell as management responsibility of the distribution channel for Tianma AMLCDproducts in the Americas. (These are theresponsibilities currently managed by Renesas Electronics America’s Display Business Unit. n
ID Guest Editorial Issue5 p4,50_Layout 1 9/22/2013 4:56 PM Page 50
industry expert Ken Werner set about tochronicle it all for us in his review article on3-D displays. I sometimes wonder whether those in the
media create hype or simply report it. We canprobably agree that the right answer is a mix-ture of both. In the case of OLED TVs, thepromise of the technology certainly createdenough buzz and interest to keep everyoneexcited in Vancouver. The reality did not disappoint, with another year of great demon-strations from Samsung and LG showing thefuture of OLED technology. Samsung hadOLED displays at Display Week but no bigOLED TVs this year. Only LG had them.But TV was just a small part of the story, asyou will realize when you read the reviewfrom our reporters Sven Murano and AnkeLemke. You may also note that since theexhibitions in May, both Samsung and LGhave released 55-in. curved OLED TVs to theconsumer marketplace, as reported this monthin our Industry News section.Although not as headline grabbing as
OLED and 3-D displays, flexible displayscontinue to evolve as well and in many caseshold promise for new and highly innovativeproducts to emerge. E Ink is the name every-one knows, and for good reason, but if youlook beyond this iconic brand, as author JasonHeikenfeld did, you will find a rich landscapeof innovations and recent industry develop-ments. Fortunately, Jason did his homeworkand scoured the show to bring us all the high-lights in his review article on flexible displaysand e-paper technologies.In addition to looking back, we’re looking
forward this month to the future of solid-statelighting with a pair of feature articles broughtto us by guest editor Sven Murano fromNovaled AG. Sven worked very hard on thispart of the issue and rightly deserves ourthanks. Highly complementary to each other,these Frontline Technology articles provide astrong overview of the market needs andopportunities for OLEDs as well as some concrete results in achieving record-settinglight-output efficiencies. I encourage you toread Sven’s guest editorial first. “OLED Lighting Edges Closer to Commercial Reality” offers a more complete introduction to bothfeatures.
One observation Sven makes in his columnis how competition from inorganic LEDs inthe lighting market is strong, with this tech-nology demonstrating increasing performance
levels and decreasing costs. Providing per-spective from that camp this month is ourthird Frontline Technology feature, “NewMilestones for LED Lighting” by author Martin Behringer from Osram. He discussesboth the historical evolution of LED technol-ogy and the latest advances of his team inachieving industry-leading performance incolor and light-extraction efficiency with thin-film devices. Last but not least, we welcome back author
and SID EC member Helge Seetzen, who con-tributed the second of his series of articlesfocused on successful strategies for creating,funding, and growing new technology ven-tures. This month, in “Raising Capital forTechnology Ventures,” Helge explains thenext steps to raising capital after you havebuilt the necessary foundation in your startupventure. It’s not as easy as it may look fromthe sidelines and I think you can avoid a num-ber of setbacks by learning from Helge andthe experiences of his team. This series willcontinue for several more months and I’malready excited about next month’s offering,in which Helge will talk in some detail aboutthe potential pitfalls of venture capital funding.As the leaves on the trees start to turn color,
and the summer holidays are now memoriesfor most of us, I wish you all a very prosper-ous and healthy fall season. We’ll be back ina couple of months with another issue focusedon very-high-resolution displays and digitalsignage. As always, we welcome your com-ments and suggestions for future articles inInformation Display. n
continued from page 2
Information Display 5/13 51
editorial
Display Week 2014SID International Symposium,
Seminar & ExhibitionSan Diego Convention CenterSan Diego, California, USA
June 1–6, 2014
SAVE THE DATE
Submit Your News ReleasesPlease send all press releases and new
product announcements to:Jenny Donelan
Information Display Magazine411 Lafayette Street, Suite 201
New York, NY 10003Fax: 212.460.5460
e-mail: [email protected]
J O I N S I DWe invite you to join SID to participate in shaping the future development of:
• Display technologies and display-related products
• Materials and components for displays and display applications
• Manufacturing processes and equipment
• New markets and applications
In every specialty you will find SIDmembers as leading contributors totheir profession.
http://www.sid.org/Membership.aspx
VISITINFORMATION
DISPLAY ON-LINEFor daily display
industry newswww.informationdisplay.org
ID Editorial Issue5 p2,51_Layout 1 9/22/2013 1:21 PM Page 51
Abrisa TechnologiesAdvantech US, Inc.AGC Asahi Glass (Silver Member)Applied ConceptsApplied NanotechAU Optronics Corp.
Chunghwa Picture Tubes, Ltd.Cima NanotechCLEARink DisplaysCorning Holding Japan
Dawar Technologies, Inc.DisplaySearchDontech (Gold Member)
Eldim (Gold Member)Elo TouchSystemseMagin Corp.Endicott Research GroupEpoxy TechnologyEuropTec USA
Henkel (China) Investment Co.,Ltd. (Gold Member)
IGNIS Innovation Inc.Instrument Systems (Gold Member)Intel Corp.I-PEX
Japan Display, Inc.
Merck Display Technologies Ltd.Mitsubishi Chemical Corp.
Mitsubishi Electric Corp.
NANOSYSNDF Special Light Products, B.V.NEC Corp.NextWindowNoritake Itron Corp.Novaled (Silver Member)
Ocular Optical Filters USA
Panasonic Corp.Parker ChomericsPhoto Research
Radiant Zemax (Silver Member)Rolic Technologies
Sartomer USA LLCSharp Corp.Shenzhen Leaguer Optronics Co.,Ltd.
SK InnovationSynapse Product Development LLC
Tannas ElectronicsTatsuta Electric Wire & Cable Co.Teijin Dupont Films Japan Ltd.TFD, Inc.
Universal Display Corp.
Westar Display Technologies, Inc.WINTEK Corp.
Electronic Assembly ..................19EuropTec USA..........................27Henkel Corp. ...........................C4Instrument Systems ..................C2Merck .........................................5
Ocular.......................................50Radiant Zemax..........................13Pixelligent .................................19TFD.........................................C3Touch Display Research ............18
52 Information Display 5/13
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