The Solid State Lighting Revolution
IEEE Student Meeting
April 8, 2010
2
The History of Lighting
THE CASE FOR A NATIONAL RESEARCH PROGRAM ON SEMICONDUCTOR LIGHTINGRoland Haitz and Fred Kish, Hewlett-Packard Company, Palo Alto, CA 94304
Jeff Tsao and Jeff Nelson, Sandia National Laboratories, Albuquerque, NM 87185-0601
3
Outline
• What’s an LED
• Lighting Class LEDs?
• The Future of Solid State Lighting
Semiconductors for High Brightness LEDs
Empty band
Forbidden
Full valance band
Ec
Ev
Engineered, multilayered crystal structure to efficiently convert current to light. Materials used, layer design and crystal quality determine color and efficiency
Semiconductor
Ev - valence band edge
Ec - conduction band edge
Eg
0.01
0.1
1
10
400 450 500 550 600 650 700Wavelength (nm)
InGaN AlInGaP
AlGaAs
GaAsP GaAsP GaP:N
SiC
Ultra-violet Blue Green Yellow Orange Red Infra-Red
Better
Worse
Luminous
Intensity
Low brightness LEDs
Very high brightness LEDs cover the entire visible spectrum
using 2 different III-V compound semiconductor
material systems
What is an LED
• Mixing colors can make white LED
- Red, Green, Blue LEDs used together - Blue LED plus Yellow Phosphor - UV LED plus various Phosphors
• Phosphor - a material that absorbs light at one wavelength and emits it at
another wavelength 0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
350 400 450 500 550 600
wavelength (nm)
rela
tive
inte
nsity
excitation
emission
How to Make a White LED
6
White LED Efficiency Increasing Rapidly
~ 200 Lm/WCree, 2010
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Early LED UseArchitainment (Architecture and Entertainment)
Courtesy of SolarOne
Off Grid LED Street LightingMasdar City
• Many street lighting programs
• 100% SSL buildings are starting to appear (mostly in Asia)
• Many hundreds of start-up companies in Solid State Lighting
• Generally still not ready for prime time• Lack of good standards• Very high prices• Lots of “junk LED bulbs”
Solid State Lighting – Coming fast
9
The Total Lighting Market is Huge
Global Lighting Market Size
(in billions)
2006 2011
Lamps (Front-end)
$20.9
$25.4
Fixtures (Back-end)
$81.1
$106.6
Total $102 $132
North America approximately 29% of the worldwide market
Total Lighting Equipment Market
0.0
20.0
40.0
60.0
80.0
100.0
120.0
140.0
1996 2001 2006 2011
Sale
s in
Bill
ions
$
North America Western Europe Japan China Other Asia/Pacific ROW
Source: Fredonia Group, Inc.
So there is a tremendous revenue opportunity for LEDs
This is where research is published, not peer reviewed literature
CONFIDENTIAL © 2007 Luminus Devices, Inc. All rights reserved.
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Some Examples of MR-16 LED Products
12
DOE Testing – Many product claims are misleading
Energy Efficient Lighting Systems
Lighting Systems interfaced to externalgrid & building systems
HealthComfort
InformationProductivity
Therapeutic LightingThe Right Light
where you want it
Lighting and Data at the same time
Adaptive Lighting Systems
Create a Top Down Vision with Input from All Stake Holders