the future of optical storage x rg zech (slide share)

The Future ofOptical Data StorageWill this once leading-edge storage

technology prosper in the 21st century?IEEE ICCE Conference 2012

Las Vegas, NVJanuary 13-16, 2012

< by >Richard G. Zech, Ph.D.

Consultant & Expert Witness - Computer Storage & PhotonicsPresident & Managing Principal

The ADVanced ENTerprises (ADVENT) GroupColorado Springs, CO 80906

(719) 633-4377 v [email protected]

[Special to SlideShare]

mailto:[email protected]

January 2012 (c) 2012 The ADVENT Group(c) 2012 The ADVENT Group 22

Forward/Read MeForward/Read MeThis presentation is both a review of my work on

optical data storage (ODS) futures over the past 10 years and a tutorial. The basic emphasis of this presentation is on the potential of ODS to increase significantly disc capacity. This is an exciting area for both research and product development.

Parts 1-6 of the presentation focus on the status and means for capacity increases for optical discs using the Blu-ray disc (BD) model. Part 7 is a series of appendices providing background/historical information. My original papers on ODS are available upon request.


AfterwardAfterwardI attended (partially) StorageVisions 2012, iCES 2012, and ICCE

2012 (January 08-16, 2012). Each in its own way was very useful for understanding major trends in consumer electronics.

A summary of my remarks at StorageVisions and ICCE follow:Ø Optical storage will continue to be the best choice for physical media

distribution. The likelihood of Flash memory devices displacing CD. DVD, or Blu-ray discs in the near future is minimal. However, Flash and online downloads are major competitors.

Ø Optical storage probably has a technical life of 5-10 years and a product life of 10-20 years. However, for optical storage to be competitive in theage of nanotechnology-enabled data storage products, new components and design strategies and significant investments will be required.

Ø Future optical storage will probably be modeled on Blu-ray disc, whose basic design is robust and extensible. Older concepts, such as 3D holographic memories, Millipede, etc., will never be commercially viable.


AcknowledgementsAcknowledgementsØ Dr. Curt Shuman, C.A. Shuman Inc.Ø Dr. Chris Steenbergen, CREST

(Concepts in Removable Storage)Ø Dr. Di Chen, Chen and Associates

It is my pleasure to acknowledge the important comments and opinions of the above optical storage pioneers.


Abstract/Overview Abstract/Overview (1/2)(1/2)More than 60 years have passed since Nobel-laureate Dr. Dennis Gabor (Imperial College) invented holography (1948). In 1963 PJ van Heerden (Polaroid) published his seminal paper on 3D data storage using holographic data storage principles. For the next 10 years holographic memories were touted as a replacement for all other types of memory. Sadly, after more than 10 attempts, no company has successfully commercialized the technology.In the 1960s, the development of servo-controlled optical disc systems was initiated. By the early 1970s analog video disc systems were commercially available. These were closely followed by 12" write-once (WORM) drives and media. In 1982 Sony and Philips announced the 120mm diameter compact disc (CD-DA) followed by the CD-ROM in 1984. In 1995 the DVD-ROM was announced and in 2002 Blu-ray Disc (BD). Each of these technologies increased capacity significantly and mainly supported important consumer electronics applications (CD for audio and DVD and BD for video). Also in 1995, the EIDE/ATAPI standard was promulgated, which allowed these drives to become a standard part of a PC’s storage suite. Consequently, sales grew exponentially. Other types of optical storage of various disc diameters and storage mechanisms were extant in the 1980-1990 timeframe, but few had even a marginal market success.In 2012, nearly 30 years after the introduction of the CD, classical optical data storage has perhaps reached, or even passed, both its technology zenith and market zenith. Solid state flash drives, portable hard drives, and downloading of music and video have begun to erode significantly the optical data storage market share. Moreover, optical data storage technology appears to have reached some fundamental physical limits (laser wavelength at 405nm and numerical aperture at 0.85). Some would say, in analogy to magnetic data storage, it may be optical data storage's "superparamagnetic limit."


Abstract/Overview Abstract/Overview (2/2)(2/2)The utility of optical data storage (ODS) is derived from how small a diffraction-limited laser beam can be focused for writing and reading; in other words, spot size. From basic optical theory we know that spot size is proportional to wavelength and inversely proportional to the effective numerical aperture (NA) of the imaging system. With 25GB/storage surface BD, the 405nm wavelength and 0.85 NA pretty much exhaust the basic potential of optical data storage.But like magnetic data storage, optical data storage has several non-conventional means that may permit the technology to reach new capacity plateaus. These range from multi-layer discs and near-field recording (NFR) to UV lasers, negative refraction and plasmonic lenses. There are also several consumer applications that may justify pushing disc capacity to 100GB, or more. One of them is 4K x 2K video (current HD is 2K x 1K), the standard for which is being developed in Japan and will require 100GB disc capacity. 8K x 4K (Super Hi Vision) is another possibility, which is even more capacity hungry (requires 400GB).In this presentation, the future of optical storage will be analyzed in terms of advanced technologies. The metrics will be maturity, difficulty of implementation, cost, impact on manufacturing yield, and market need. The specs and performance potential of some of these advanced optical data storage devices will be enumerated. Finally, some related data storage technologies that promise multi-TB capacities will be discussed.The engineering challenges of these advanced optical read/write methods on lasers, media, optical pickups, servos, and read/write channels will be significant, but achievable. They must be done if optical data storage is to survive. Then, one can confidently predict the future of optical storage will be for capacities reaching 1 TB.


ContentContentØ Part 1: IntroductionØ Part 2: Near-term PossibilitiesØ Part 3: At the Mountains of MadnessØ Part 4: Some Key Enabling TechnologiesØ Part 5: Replication and Disc Manufacturing

ChallengesØ Part 6: Summary, Conclusions, &

RecommendationsØ Part 7: Appendices

Part 1Part 1

Introduction


Some General AssumptionsSome General AssumptionsØ Blu-ray Disc (BD) Model (25GB per surface) and Other

Main SpecificationsØ 120mm Diameter Discs (except for X-ray “ODS”)Ø Recording radii of 22mm ~ 58mm (storage area of about 14in2)Ø Single Surface Disc with 1TB capacity requires an

areal storage density of about 572Gb/in2

Ø Replicated, Write Once, or Rewritable Phase Change Storage Layers

Ø Single- and Multi-Layer Disc ArchitecturesØ Single- and Multi-Level Disc Surface EncodingØ Front Surface Read and WriteØ Data rates will scale with recording (bit) density.


Optical Data Storage has come a longOptical Data Storage has come a longway in the past 42 years!way in the past 42 years!

WorldWorld’’s First MO Optical Disc Recorders First MO Optical Disc RecorderMnBi film coated optically flat disc on air bearing spindle, with HeNe laser, EO modulator, and galvo deflector. Honeywell Research Center, 1969 (Dr. Di Chen, Ref 1)


The ODS Product Technology Cycle

(The CD Era)(The CD Era)

(The DVD Era)(The DVD Era)(The BD Era)(The BD Era)

(Significant Competition)(Significant Competition)(Breakthrough (Breakthrough Technologies)Technologies)

(End of ODS Products)(End of ODS Products)[OR][OR]


Optical Storage's “Moore's Law”

source: Dr Chris Steenbergen, CRESTThe symbol ▌in this slide means λ.


Optical Disc Capacity Optical Disc Capacity -- AchievedAchieved

not nanotech18.1227,29311214979,37532025BD

(G3)

not nanotech3.2795,13126740034,3247404.7DVD

(G2)

not nanotech0.68343,05159083315,8751,6000.65CD

(G1)

CommentCommentAreal Areal

DensityDensity(Gb/in(Gb/in22))

Recording Recording DensityDensity

(bpi)(bpi)

Data Data Bit Bit

Length Length (nm)(nm)

Min. Min. Mark Mark SizeSize(nm)(nm)

Track Track density density

(tpi)(tpi)

Track Track Pitch Pitch (nm)(nm)

CapacityCapacity(GB)(GB)TypeType

The above table summarizes existing ODS technologies, all backed by recognized book specifications and in production. G = Generation.


Classical Optical Storage Classical Optical Storage -- IIIs the end of the technology line in sight?Is the end of the technology line in sight?

Ø Laser diode (LD) wavelengths (λ) have reached the end of the visible spectrum at 405nm.

Ø Conventional objective lenses have reached the limit of usable numerical apertures (NAs) at 0.85.

Ø Spot size is proportional to λ/NA; shorter λs and larger NAs yield smaller spot diameters and higher areal densities ~ (λ/NA)2.

Ø The technology life appears ended - But Wait!This is only true for linear thinking and design.


Classical Optical Storage Classical Optical Storage -- 22Is the end of the technology line in sight?Is the end of the technology line in sight?

Ø For λ fixed at 405nm and NA=0.85 (BD model), classical optical storage can increase capacity in several ways, alone or in combination.

Ø Architecture Examples:– Multi-Layer Disc (MLD); 2N surfaces.– Multi-Level Recording (MLR); replicated, phase change.– Near-Field Recording (NFR); read-only and write/read.

Ø Attractive Combinations:– MLD + MLR (25GB/surface x 2.5 ML gain x N surfaces or

250 GB/120mm disc).– NFR + MLD + MLR (50-200GB/surface x 2.5 ML gain x 1-2

surfaces or 125GB - 1TB/120mm disc).The above are the lowest risk, lowest cost strategies.

Part 2Part 2

Near Term Possibilities


ODS Prospects 5ODS Prospects 5--10 years Ago10 years AgoØ Multi-Layer Recording

– Increases capacity without requiring a corresponding increase in areal density.– 4-, 8-, 12-, 16-layer discs with up to 400 GB capacity demonstrated by Philips, Pioneer, and TDK

using Blu-ray storage layers.– Increases optical media manufacturing and replication costs significantly.

Ø UDO– 30 GB cartridges shipping today; 60 GB cartridges expected in 2007, but came in 2009.– A blue-laser concept, but not Blu-ray (computer application oriented).– Roadmap capacity to 120 GB/cartridge.

Ø Near-field Recording (NFR)– Multiplies effective NA.– Maximizes areal density and surface capacity.– Trades MLD complexity for optical head-disc interface complexity.

Ø MultiLevel Recording (MLR) – not to be confused with multi-layer disc (MLD)– Provides a practical 2.5x bit density multiplier per layer (8 levels).– Can be implemented with a single DSP; not too expensive.– Works with any optical storage recording technology.

Ø 3-D Holographic Memories (Holomems) - Disc Architectures– Products after 48 years of worldwide R&D were expected by end of 2010; it didn’t happen .– Mainly professional AV storage, archiving, and some general applications.– Only two real players: InPhase Technologies & Optware (Japan) – both now out of business.

Ø Fluorescent Multilayer Disc (FMD)– Great concept (discrete layer 3-D storage), but some inherent problems.– Constellation 3D (out of business) needed some heavyweight funding for product development.– Excellent HDTV playback demonstrated for 6-layer disc.


Disappointments/Possible Write OffsDisappointments/Possible Write Offs--A 2012 PerspectiveA 2012 Perspective

Ø Magneto-Optical (MO)Ø 3D HolomemsØ Fluorescent Multilayer Disc (FMD)Ø UDO (Ultra Density Optical)Ø Bit-oriented MemoriesØ Probe/Cantilever (similar to IBM’s “Millipede”)Ø Biological (biorhodopsin and similar)

The above technologies either don’t fit a market need (price/performance issues), are too expensive, cannot be reliably implemented outside the lab, are a technology dead end, or all the above.


Future ODS Technologies (?)Future ODS Technologies (?)→ Near-Term (getting to 100GB/120mm disc)

– Multi-Layer Architecture (with and without Multi-Level Encoding)

– Near-Field RecordingOver the Horizon (getting to 1TB/120mm disc)

– UV Disc– X-RAY Disc– Atomic/Quantum Mechanisms (not really

optical, but could use optical disc architectures)


2a) Multilayer Disc


BluBlu--ray Disc Standard Referenceray Disc Standard Reference

Source: Philips

(1 or 2 layer)(1 or 2 layer)


BluBlu--ray Disc Roadmapray Disc Roadmap

Source: TDKSource: TDK


Isao Ichimura, et. al., SONY, JapanIsao Ichimura, et. al., SONY, Japan


2b) Near-field Recording


Note: An effective NA of Note: An effective NA of ~ 1.7 doubles bit and track densities. BD ~ 1.7 doubles bit and track densities. BD model capacity increases by a factor of 4x (to ~ 100 GB). Graphmodel capacity increases by a factor of 4x (to ~ 100 GB). Graphic ic source: Philips NV.source: Philips NV.


NearNear--Field Recording with VSALsField Recording with VSALs(source: Lucent Technologies)(source: Lucent Technologies)

λ

NEAR FIELD

Near Fie ld

d / 2

d

VSAL = Very Small Aperture LaserAperture Size Determines Resolution -- Independent of Laser Wavelength

Exceptionally Small Spot Sizes -- 60nm spots (134Gb/in2) demonstrated in MO materialBeam of any shape demonstrated -- Improves performance & design flexibility

Near-Field image of 60 nm bits written by near-field compared with Far-Field


2c) Multi-Level TechnologyØ Multi-Level (ML) is not a product, but a

performance-enhancement technology.Ø Fixed-size data cells support 8 reflection levels or

variable areas on a dye-polymer (±R) or phase change (±RW) recording layer. Yields about 2.5 bits per cell in practice (not the theoretical 3).

Ø ML-enhanced drives and media work for CD/DVD and Blue-laser formats. Should work for all disc formats.

Ø 2GB “CD-ROM” shipped by TDK ~ 2001; very little market acceptance.

Ø 60GB per 120mm Blue Disc demonstrated in lab (Calimetrics, now part of LSI Logic, and Philips joint research project). The enabler was a proprietary DSP chip (core IC) from Sanyo. Circa 2002.

Part 3Part 3At the Mountains of

Madness*Bleeding Edge Futures

*After HP Lovecraft’s Novella about terror in the mountains of Antarctica.


Extending the DefinitionExtending the Definitionof of ““OpticalOptical””

Ø Classically, “optical” means electromagnetic radiation having wavelengths (approximately) in the 400nm-700nm range.

Ø ODS has reached the classical technology end of life with BD discs and drives at λ = 405nm (and NA = 0.85).

Ø However, extending the meaning of “optical”to include UV and X-radiation, opens new frontiers for high-density data storage.


Potential Optical Disc Capacity Roadmap(?)Potential Optical Disc Capacity Roadmap(?)

real nanotechNano-

imprinting?658.21,554,80316.322.9423,333601,0007G

(2024?)

real nanotechEB Mastering?329.11,036,53524.534.4317,500805006G

(2020?)

"nanotech threshold"

EB MasteringNear-Field Read

144.8615,68641.358235,1851082205G(2016?)

4-layer or NFR“not nanotech”18.1227,29311214979,3753201004G

(2012?)

CommentCommentAreal Areal

DensityDensity(Gb/in(Gb/in22))

Recording Recording DensityDensity

(bpi)(bpi)

Data Data Bit Bit

Length Length (nm)(nm)

Min. Min. Mark Mark SizeSize(nm)(nm)

Track Track density density

(tpi)(tpi)

Track Track Pitch Pitch (nm)(nm)

CapaCapacitycity(GB)(GB)

TypeType

4G and 5G are proven in the lab. 6G and 7G (following the BD model at a higher areal density) are pure speculation, but illustrate the challenges faced by optical storage to reach 1 TB capacity. Multi-layer solutions are feasible. 4-layer, 8-layer, 12-layer, and 16-layer discs are proven in the lab. NFR is also feasible, but needs to be proven outside the lab. The real potential of nanotech is yet to be determined.


Tracks and Pits for Electron Beam Mastering Tracks and Pits for Electron Beam Mastering (5G?) (5G?) -- Near Field ReadNear Field Read

120mm Capacity = 220 GB; storage density = 144.8Gb/in2. The track pitch is 108nm; the minimum mark size is 58nm. This is at the nanotechnology threshold. (source: Sony Corporation)


Future ODS Technologies (?)Future ODS Technologies (?)Near-Term

– Multi-Layer Architecture (with and without Multi-Level Encoding)

– Near-Field Recording→ Over the Horizon

– UV Disc– X-RAY Disc– Atomic/Quantum Mechanisms (not really

optical, but could use a disc architecture; that is, may require a read/write head, servoing, etc.)


Potential Future ODS TechnologiesPotential Future ODS TechnologiesØ UV disc (continuation of the classical optical roadmap - requires UV

laser diodes)Ø X-ray disc (digital holography means)Ø Atomic/Molecular (data storage by means of configuration or

quantum state or both, but may share implementations like “optical.”)Ø Some enabling means:

– negative refraction (spot sizes less than the diffraction limit)– variable focus lenses (for multi-layer discs to correct for

spherical aberration)– nanotech (e.g., super high storage densities, self assembly,

patterned media)– nanophotonics (e.g., modulators, lasers, gratings implemented in

Silicon)– plasmonics (spot sizes less than the diffraction limit)– photon sieves (for far UV and X-ray spot formation)


3a) UV 3a) UV ““Optical StorageOptical Storage””


Ultraviolet Ultraviolet ““OpticalOptical”” StorageStorageØ Does classical optical data storage end with λ = 405nm?Ø Not if the technology uses near and mid-range ultraviolet (UV).Ø Diagnosis: UV optical storage will be far more challenging than

near-IR and visible optical storage ever was.Ø Front surface recording layer and reflection component OPU

(optical pickup unit) required.Ø Prognosis: Within 5 years optical storage at λ = 325nm (e.g.,

frequency doubled 650nm) will be feasible. This increases the capacity per layer to 39GB - 3 layers are needed to reach 100GBcapacity per disc.For λ = 202.5nm (e.g., frequency doubled 405nm; vacuum UV regime), the trade offs involve a 4x increase in BD areal density, versusthe complexity and cost of UV components. This increases the capacity per layer to 100GB – only 1 layer is needed. However, the technology will probably be abandoned before reaching λ = 202.5nm, owing to cost and complexity.

Ø Much of UV optical storage technology will probably be adapted from semiconductor UV and EUV lithography.


UV UV ““OpticalOptical”” Storage ChallengesStorage ChallengesØUV laser diodes (expensive today, low power)ØUV optical components (need reflective

optical elements for OPU)ØUV storage media (media noise may be a big

problem)ØCost and complexity (may not be proportional

to capacity increase)ØMastering and replication processesØKiller application motivation


UV Laser DiodesUV Laser DiodesØ UV laser diode technology is still immature.Ø Very few commercial products are available.Ø Engineering samples from Nichia have 200mW CW output @

375nm.Ø 340nm-360nm is current R&D sweet spot. 240nm-260nm

demonstrated in the lab.Ø DPSS (diode-pumped solid state) lasers, which can be

frequency tripled or quadrupled, must be greatly reduced in size and cost to be candidates.

Ø Other options to UV laser diodes and DPSS (for example, KrF or F2 fiber) have no possibility of meeting size and cost requirements.

Ø Nanotech may hold the key to long-term prospects (structural enhancements, materials improvements).

Ø Bottom Line: UV laser diodes are in about the same position as blue lasers in 1995. Solutions are 3-5 years out.


3b) X3b) X--RAY RAY ““Optical StorageOptical Storage””


XX--Ray Ray ““OpticalOptical”” StorageStorageWRITEØ Concept designed for x-radiation with λ ≤ 1nmØ 1D or 2D computer-generated Fourier Transform hologramsØ Select page size (N or NxN pixels) and offset angleØ Compute and sample analog interference patternØ Apply data coding and EDACØ Modulate and scan write spot to form hologramREADØ Parallel read by means of holographic reconstructionØ Position read beam over hologramØ Project N or NxN pixels onto photodetector arrayØ Process and format serial data stream


XX--Ray Ray ““OpticalOptical”” StorageStorageThe ChallengesØ A compact, safe, inexpensive X-ray laser.Ø All optics must be reflective.Ø No compact photodetector arrays.Ø New mastering (write) and replication methods required.The AdvantagesØ No page composer (SLM) required.Ø No 3D media and incoherent superposition (stacking) of

holograms required.Ø Can apply method to all media formats.Ø Read servo requirements about the same as today’s DVD.


XX--Ray Ray ““OpticalOptical”” StorageStoragePerformance Potential of Digital Fourier Transform Holograms:

Ø Assume a disc format; 50mm diameter and a recording area of 1600mm2.

Ø Storage Density ρ = 1/(2λF#)2

Ø For λ = 0.5nm and F# = 2, ρ = 250Gb/mm2

(160Tb/in2)Ø C = 50TB unformattedØ Access Time < 10msØ Read Data Rate = function of [# of pixels,

read power, detector sensitivity, scan speed]; could achieve 50Gbps, or higher.


StateState--ofof--thethe--Art XArt X--Ray LaserRay LaserA FreeA Free--Electron Laser (FEL)Electron Laser (FEL)

Some engineering required to make suitable for optical storage aSome engineering required to make suitable for optical storage applicationspplications

Source: University of Hamburg


3c) StarTrek Era Storage3c) StarTrek Era Storage


Bits Written on Ferroelectric Thin FilmBits Written on Ferroelectric Thin Film

The marks are roughly on 25nm centers corresponding to a storage density of about 1TB/in2. Writing and reading are done by means of a voltage nanoprobe.The storage mechanism is domain switching between two polarization states. Imaging is done via a DC-EFM (Dynamic Contact-Electrostatic Force Microscopy).


Density = 645Density = 645Tb/inTb/in22. 113. 11300TBTB (unformatted) (unformatted) on a 120on a 120mmmm disc.disc.[Assumes 1[Assumes 1nmnm bit and track pitches.]bit and track pitches.]


(51.6 Pb/in(51.6 Pb/in22))

H = Hydrogen atomH = Hydrogen atom

F = Fluorine atomF = Fluorine atom

StorageStorage at the atomic level. In this concept H atomsat the atomic level. In this concept H atomsrepresent 0s and F atoms represent 1s.represent 0s and F atoms represent 1s.

Part 4Part 4

Some Enabling Some Enabling TechnologiesTechnologies


A Few ExamplesA Few ExamplesØ Plasmonic OPU (POPU)Ø Negative RefractionØ Variable Focus Lenses (needed to aid layer-to

layer focusing for ML discs)

Ø Photon SievesThe above enabling technologies may provide the means to write/read significantly smaller marks.


Plasmonic Optical StoragePlasmonic Optical Storage


Plasmonics for ODSPlasmonics for ODSØ Plasmonics is a branch of physics in which surface

plasmon resonances of metals are used to manipulate light at the sub-wavelength scale.

Ø Surface plasmon polaritons (SPPs) are collective oscillations of electron density at an interface of a metal and dielectric.

Ø Because SPPs can be excited and strongly coupled with incident light, they have many potential applications in high-resolution optical imaging and storage and lithography.

Ø Some metals (gold and silver, for example) exhibit strong SPPs resonance in certain wavelength ranges, and therefore can be used to guide and concentrate light to nanoscale spots less than the classical diffraction limit.

Ø Some of the SPPs resonant structures can produce a field irradiance (W/m2) at the near field that is greater by orders of magnitude than the incident light.

Ø Some resonant optical antennas can concentrate laser light into < 25nm FWHM size spots (as defined by gap widths).


Plasmonic Optical Pickup Unit (POPU)Plasmonic Optical Pickup Unit (POPU)Ø Optical read/write similar to NFR; that is, a POPU is required

that flies 20nm, or lower, above the disc surface. Hence, an ABS is required to achieve this.

Ø Spot sizes can be 25nm FWHM, or smaller. This corresponds to an areal density of ≈ 1Tb/in2, or a capacity of ≈ 1.75TB on a 120mm disc. Initially, a 70x increase versus Blu-ray Disc.

Ø Will permit multi-channel read/write.Ø Will permit integrated POPU.Ø Will support head per side optical disc drives.Ø Major challenges will be servo control of POPU flying height

and tracking.POPUPOPU = Plasmonic Optical Pickup Unit / = Plasmonic Optical Pickup Unit / NFRNFR = Near= Near--field Recordingfield Recording

ABSABS = Air Bearing Surface / = Air Bearing Surface / FWHMFWHM = Full Width Half Max= Full Width Half Max


PlasmonicsPlasmonicsResonant Optical Antenna DesignsResonant Optical Antenna Designs

See ReferenceSee Reference 5.5.


PlasmonicsPlasmonicsLaser Antennas & Spot FormationLaser Antennas & Spot Formation

See Reference 5See Reference 5..


A MultiA Multi--Channel POPU for ODSChannel POPU for ODS

See Reference 6. Modified by the author for ODS applications.See Reference 6. Modified by the author for ODS applications.


Parallel Track Read/WriteParallel Track Read/Write

See Reference 6.See Reference 6.


Negative Refraction


Negative RefractionNegative Refraction

source: Physics Today (December 2003)source: Physics Today (December 2003)a) negative refraction b) normal (positive) refraction



normal refraction

negative refraction


Variable Focus Lenses


Variable Focus LensesVariable Focus Lenses



source: http://physicsweb.org (Feb 3 2006)source: http://physicsweb.org (Feb 3 2006)

http://physicsweb.org

http://physicsweb.org



source: Photonics Spectra, March 01 , 2005


Photon Sieve“Fourth generation light sources, based on Free-Electron Lasers (FEL) will be capable of producing X-rays of such extreme brilliance that new possibilities of focusing the radiation emerge. An optical element, based on the simple concept of an array of pinholes (a photon sieve), exploits the monochromaticity and coherence of light from a free-electron laser to focus soft X-rays with unprecedented sharpness (high irradiance levels). The combination of an excellent focus with extreme flux will providenew opportunities for high-resolution X-ray microscopy and spectroscopy in both the physical and life sciences.” From http://www.photonsieve.de/

(Also works for visible and UV light). Google “photon sieve.”

SeeNature 414, 184 -188 (2001)Research supported by the BMBF, Germany Protected by patents (see, for example, US7368744 re Photon Sieve for Optical Systems in Micro-lithography)

http://www.photonsieve.de/


Photon SievePhoton SieveA means for focusing UV and X-ray beams to sub-diffraction spots

source: http://www.photonsieve.de/source: http://www.photonsieve.de/




Photon SievePhoton SieveIrradiance profile of the photon sieve is on the left;Irradiance profile of the photon sieve is on the left;

its Gaussian counterpart is on the right.its Gaussian counterpart is on the right.

source: http://www.photonsieve.dehttp://www.photonsieve.de

[Note the suppression of the secondary maxima by the photon sieve]

http://www.photonsieve.de

http://www.photonsieve.de

Part 5Part 5Replication and Disc

Manufacturing


Mastering & ReplicationMastering & ReplicationØ The future of optical disc storage will ultimately be

determined by disc mastering and replication processes.

Ø Near-UV mastering and modified replication processes already exist. Phase transition mastering at 405nm works well for BD.

Ø For C ≥ 100GB per layer/120mm disc, extreme UV (EUV) or e-beam mastering machines (EBMM) will be required.

Ø EBMM have already achieved 50nm wide pits (DVD uses 300nm); 15nm features are feasible.

Ø 100GB (recordable/rewritable) and 200GB (read-only) per layer for 120mm discs have been demonstrated at the research level.


Optical Disc MasteringOptical Disc Mastering-- AFM ImagesAFM Images

(source: Optical Disc Corporation – achieved more than 10 years ago)


This process is an invention This process is an invention of Plasmon plc in 1986. of Plasmon plc in 1986. Company researchers used Company researchers used largelarge--diameter, collimated diameter, collimated ArgonArgon--ion laser beams to ion laser beams to create a grating master on a create a grating master on a 130mm130mm diameter glass diameter glass substrate. An array of subsubstrate. An array of sub--micron cells was create by micron cells was create by rotating the substrate by 90 rotating the substrate by 90 deg and repeating the deg and repeating the exposure. The crossed exposure. The crossed gratings were the basis for gratings were the basis for PlasmonPlasmon’’s s ““mothmoth’’s eyes eye””writewrite--once optical media, once optical media, which closely approximated which closely approximated an ideal black body.an ideal black body.


Challenges & Opportunities forChallenges & Opportunities forthe Optical Media Industrythe Optical Media Industry

Ø The technology and equipment for CD and DVD is proven and mature. The key problems for BD have been solved. That was the easy part.

Ø Optical media in the next generations will be more complex. Required yield, throughput, and quality will be harder to achieve, regardless of the future technology winner(s).

Ø The cost and complexity of processes and equipment and the unit cost of media will increase, perhaps significantly in some cases. A major challenge to the industry is to prevent or minimize this.

Ø New or modified processes, manufacturing equipment, and quality control methods will be required for N-layer MLD and NFR media.

Ø More sophisticated and complex in-line and off-line test and measurement equipment will be required.

Ø The cost of R&D will increase significantly; more materials scientists, chemists, and physicists will be needed.

Ø On the positive side, new opportunities are plentiful, and provide a natural evolutionary path. On the negative side, a finite probability exists that increasing the capacity of optical storage media may well become too expensive (diminishing economic returns).

Part 6Part 6

The Bottom Line


Summary and Conclusions 1Summary and Conclusions 1Ø The market success of optical storage products can be

correlated with design to a specific application (notably audio or video). CD, DVD, and Blu-ray Disc (BD) are the most relevant examples.

Ø Computer applications were extensions for CD (CD-ROM), inherent, but secondary for DVD and BD.

Ø If consumer applications no longer require optical discs, ODS will then depend on computer storage applications.

Ø Existing optical storage technologies still have at least a 10-year useful product life cycle. However, classical optical storage will have reached the end of its technology life before then.

Ø Future ODS products will primarily be the blue-disc progeny of Blu-ray Disc.


Summary and Conclusions 2Summary and Conclusions 2Ø Optical storage 5-10 years from today will be provided mainly

by evolved versions of today’s proven technologies.Ø Optical storage will continue to dominate the removable-media

AV applications sector in consumer electronics for the near future. "HDTV" playback and recording and personal storage applications will remain the dominant applications.

Ø Over the 10-year horizon, optical storage will likely be provided by a mixture of today’s evolving and future technologies. Displacement technologies cannot be ruled out.

Ø To secure its future in the mainstream storage world, ODS must expand its horizons. This will require significant investment and risk, given its many challenges and competitors.


RecommendationsRecommendationsØ Anyone in the ODS drive or media business,

whether OEM or ODM, should accept the certainty that ODS technology is at a tipping point.

Ø Optical Media manufacturers must develop equipment that can handle spatial structures of less than 50nm and inline manufacturing of 4-16 layer discs.

Ø Future ODS products will have a large percentage of what today are considered esoteric components; most have not been developed to commercial status – R&D must focus on “future” components, if future ODS products are to be evolved.

Part 7Part 7

Appendices


< Appendix 7A >< Appendix 7A >About the AuthorAbout the Author

Dr. Dick Zech has over 46 years of computer storage, materials science and photonics experience. His academic focus was on modern optics, electromagnetic theory, communications theory, advanced mathematics, and the chemistry/physics of materials. His doctoral dissertation was entitled "Data Storage in Volume Holograms” (supervised by Prof. Emmett N. Leith at the University of Michigan). His primary expertise is in the fields of optical data storage, holography, recording media, nanotechnology, optics, and optical disc replication processes and technology. His main interests are data storage; lasers; materials physics, chemistry and processes; control and positioning of light beams; and photonic components and their integration into fully functional information processing systems.

Much of Dick’s early work (1965-1979) was for the US Department of Defense, NASA and various intelligence agencies. The primary goal of this work was to use photonics technology for the rapid acquisition, processing, storage and communication of data vital to national defense and the space program (including holographic wideband recorders and BORAM holographic memories) . In addition, Dick also has significant engineering, product and business development, and sales and marketing management experience, which he has used as a consultant for the past 23+ years. Since 1990 he has worked as an expert witness in numerous patent infringement litigations (and a few involving breach of contract and theft of trade secrets) and evaluated over 200 patents for technical and economic merit. Among his inventions are the projected real-image Lippmann-Bragg hologram, volume manufacturing methods for holograms, and the multi-channel optical disc recorder (DIGIMEM). He has published over 150 papers, reports, and presentations.


< Appendix 7B >< Appendix 7B >ReferencesReferences

1. Di Chen and R.G. Zech, Optical Data Storage - Technology and Business Outlook (Invited Paper), International Forum on OpticalIndustry IP (Cheng Chan High Tech Center), Shanghai, China, May 19-21 2007.

2. "Relevant Technologies for Future Generations of Optical Data Storage," Prof. M. Mansuripur (Optical Sciences Center, Un. of Arizona), Media-Tech Conference, Hollywood, CA, August 31, 2004.

3. "Optical Recording at 1Tb/in2," Prof. T. D. Milster, (Optical Sciences Center, Un. of Arizona), THIC Meeting, Louisville, CO, July 22-23, 2003.

4. Harumasa Yoshida, Yoji Yamashita, Masakazu Kuwabara & Hirofumi Kan, Nature Photonics 2, 551 - 554 (2008) Published online: 27 July 2008.

5. Using Plasmonics to Shape Light Beams, OPN, May 2009, pp. 22-27.6. High-speed Nearfield Optical Recording Using Plasmonic Flying Head,

Liang Pan et al, NSF Nano-scale Science and Engineering Center, University of California (Berkeley), Paper OMA3, NLO/ISOM/ODS 2011.


< Appendix 7B >< Appendix 7B >ReferencesReferences

Some of Dick Zech's papers:Ø “Volume Hologram Optical Memories: Mass Storage Future Perfect?,” Optics and Photonics News, August 1992, pp.

16-25.Ø “Where do we go from here? Digital Media Futures for Consumer Electronics,” Diskcon 2002, , San Jose, CA,

September 17-19, 2002.Ø “UV Futures for Optical Disc (What’s Next for DVD after Blu-ray?),” adapted from the International Storage Industry

Consortium (INSIC) 2003 Conference on the Future of Optical Data Storage, San Francisco, CA, January 23-25, 2003.Ø “Technology Analysis: Optical Storage Futures - The Consumer Electronics Perspective," IIST Workshop XVII,

Asilomar Conference on Computer Storage, Monterrey, CA, December 2003.Ø "Strategic Assessment of Next Generation and Future Optical Storage Technologies,“ National Electronics

Manufacturers Initiative (NEMI) Biannual Roadmap, July 2004. Ø The 2005-15 Roadmap: Optical Storage for Consumer Electronics," An ADVENT Special Report, December 2004.Ø "A Bright Future for Optical Storage - The Consumer Electronics Perspective," Storage Visions 2005, Las Vegas, NV,

January 4-5, 2005.Ø "Focusing on Blu-ray & HD DVD," The 2006 Consumer Electronics Show, Las Vegas, NV, Jan 5-8, 2006. Ø "The Blue-Laser Media Perspective," A CeBIT 2006 Summary Report, Hannover, Germany, March 8-15, 2006. Ø "Strategic Assessment of Next Generation and Future Optical Storage Technologies," international National

Electronics Manufacturers Initiative (iNEMI) Biannual Roadmap, July 2006. Ø "The Future Direction of Optical Data Storage: Technologies and Challenges in the 21st Century (Invited Paper),"

Media-Tech 2006, Long Beach, CA, October 10-11, 2006. Ø Computer Storage at the New Technology Tipping Point: The Impact of MEMS and NEMS on Performance (Invited

Paper)," International Conference on Consumer Electronics 2007, Las Vegas, NV, January 10-14, 2007. Ø A DVD Primer - The DVD-Video Perspective (rev 08), An ADVENT Group Publication, September 2007.Ø “Optical Data Storage: A Tutorial (Invited Paper),” International Conference on Consumer Electronics 2009, Las

Vegas, NV, January 11-14, 2009.

Copies of ZECH publications available in PDF format upon request by e-mail to [email protected].

mailto:[email protected]


< Appendix 7C >< Appendix 7C >33--D Holographic MemoriesD Holographic Memories

(Holomems)(Holomems)


Holographic MemoriesHolographic Memories


Holographic Memories Holographic Memories -- HistoryHistoryØ Original concept by P.J. van Heerden (Polaroid) in 1963, based on D. Gabor’s

“wavefront reconstruction” (holography).Ø Generally agreed to be impractical by 1975.Ø Over 50 companies worldwide have invested in and abandoned the technology

(1965-2010).Ø The early 1990s saw a resurgence in interest; for example, DARPA’s

HDSS/PRISM program helped to greatly advance the art.Ø The “no moving parts” (random access) BORAM model has been abandoned in

favor of the (direct access) optical disc model.Ø Advances in lasers, storage media, photodetector arrays (PDAs), spatial light

modulators (SLMs), hologram stacking methods, data coding, and signal processing have made 300GB 130mm discs feasible today.

Ø Today’s leading companies are InPhase Technologies and Optware (Japan).Ø After more than 40 years of R&D, holographic memories (holomems) in 2009

appeared on the threshold of commercial viability for a limited set of applications (for example, general archiving and digital video storage). Both companies now out of business.

Ø Holomems are not suitable for consumer electronics applications today. However, they could have effectively supported the creation and delivery processes.


Pros and Cons of HolomemsPros and Cons of HolomemsProsØ Parallel write/read of large data pages (1024 x 1024 pixels common).Ø 3D stacking of holograms in a common volume (increases 2D areal

storage density by a factor of 1,000x, or more).Ø Simple read mechanisms, which reconstruct each data page

independently (ideally, with no crosstalk).

ConsØ Complex system designs.Ø Demanding storage media requirements.Ø Lack of infrastructure (photonic components challenging; optical

communications applications have driven lower pricing, volume, and reliability).

Ø Expensive hardware compared to competing storage technologies (disc media competitive).


IBM Demon 2IBM Demon 2Holomem DemonstratorHolomem Demonstrator

source: IBM Almaden Labs


Optware Holomem ProductsOptware Holomem Products

Optware tabletop exhibit at ODS 2004 Optware tabletop exhibit at ODS 2004 (source: ADVENT)(source: ADVENT)


InPhase Technologies PrototypeHolomem Drive and Disc Cartridge

source: InPhase Technologies


InPhase TechnologiesInPhase TechnologiesHolomem Drive SchematicHolomem Drive Schematic

HWP = half wave plate SLM = spatial light modulator HWP = half wave plate SLM = spatial light modulator source: InPhase Technologies source: InPhase Technologies

(record optical path) (read optical path)


InPhase Holomem Recordable Technology "Roadmap"InPhase Holomem Recordable Technology "Roadmap"

1.51.51.5Material Thickness (mm)

407

100

700,000

1696x1710

1200x1200

1st

0.65

1,600

2560 Gb/in2

960 Mbits/s

2010

7050Laser power (mW)

350,000176,000Camera sensitivity (Counts/(J/m2))

1696x17101280x1024PDA Pixels

407407Wavelength (nm)

0.650.65NA of object beam

2nd2ndBragg Null

800300Estimated Capacity (GB)

1200x12001280x1024SLM Pixels

1280 Gb/in2

640 Mbits/s480 Gb/in2

160 Mbits/sEffective Areal DensityRaw Data Rate

20082005Specs

Original table from InPhase; edited by the author to show capacity points for 130mm discs.


source: Maxell


< Appendix 7D >< Appendix 7D >Fluorescent MultilayerFluorescent Multilayer


Fluorescent Multilayer Disc (FMD)

Ø 5-100 storage layers on a substrate (claimed; about 20 actual)Ø Read signal generated by laser-induced linear or non-linear fluorescenceØ Minimal interaction between layers (adequate signal and SNR)Ø Gives optical storage equivalent HDD multiple discs per spindle capabilityØ No standards issues (works with CD, DVD, and BD/HD DVD media formats)Ø Read Only, Write Once, and ReWritable storage modes are possibleØ Drives are feasible (may need dynamic aberration correction)Ø Disc manufacturing is complex, likely to be expensive initially, but feasibleØ Inventor C3D went out of business, but came back as D Data Inc (New

York).


< Appendix 7F >< Appendix 7F >Ultra Density Optical (UDO)Ultra Density Optical (UDO)


UDO UDO -- The Other BlueThe Other Blue--laser Disclaser Disc

Ø UDO = Ultra Density Optical (a Plasmon plc product – the company is no longer in business)

Ø Original design by Sony as successor to 5.25" MO.Ø Designed for computer applications (-R and -RW).Ø 30 GB cartridge media (2-sided phase change disc).Ø ANSI-standard 5.25" MO disc cartridge; jukebox

ready.


Source: Plasmon plc


source: Plasmon plc

the future of optical storage x rg zech (slide share)

Technology

future optical storage

optical storage pioneers

magnetic data storage

removable storage

storage mechanisms

optical data storagetechnology

optical disc systems

enabled data storage