paul s. martin - 12feb03 ieee santa clara final for...

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11 Copyright (c ) Copyright (c ) Lumile ds Lumile ds Lighting LLC Company Confide ntialLighting LLC Company Confide ntial

Illumination with LEDs

Paul S. MartinPaul S. Martin

www.lumileds.com

IEEE Santa Clara – February 12th 2003

22 Copyright (c) Copyright (c) Lumileds Lumileds Lighting LLC Compan yLighting LLC Compan y

OutlineOutline• Introduction to Lumileds Lighting☺

•• LED Technology & metricsLED Technology & metrics

•• Options for making white light from Options for making white light from LEDsLEDs

•• Competition in the market for Illumination Sources Competition in the market for Illumination Sources Incandescent & Fluorescent Bulbs.& Fluorescent Bulbs.

•• Lumileds power LED in BacklightingLumileds power LED in Backlighting

•• Some interesting demosSome interesting demos

High Power White LEDsHigh Power White LEDs

2


Lumileds’ Parents

50/50 Joint Venture between Agilent Technologies and Philips Lig50/50 Joint Venture between Agilent Technologies and Philips Lightinghting

Philips Lighting: Philips Lighting: The world leader in lightingThe world leader in lighting

HP/Agilent: HP/Agilent: 40 years heritage in LED technology leadership40 years heritage in LED technology leadership


Lumileds Worldwide Lumileds Worldwide

The NetherlandsThe NetherlandsSan Jose, CA, USA. HeadquartersSan Jose, CA, USA. Headquarters

PenangPenang, Malaysia, Malaysia

~600 People and $150M in Revenue

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Who is LumiLeds?Who is LumiLeds?

Fully integrated light source supplier that co-develops optimized system solutions

•• LED diceLED dice

•• LuxeonLuxeon Power Light SourcesPower Light Sources

•• Arrays of High Flux LEDs on Arrays of High Flux LEDs on a metal core PCBa metal core PCB

•• AutomotiveAutomotive Traffic SignalsTraffic Signals Outdoor SignageOutdoor Signage


OutlineOutline•• Introduction to Introduction to Lumileds Lumileds LightingLighting☺☺

• LED Technology & metrics

•• Competition in the market for Illumination Sources Competition in the market for Illumination Sources Incandescent & Fluorescent Bulbs.Incandescent & Fluorescent Bulbs.

•• Options for making white light from LEDsOptions for making white light from LEDs

•• Lumileds power white LED performanceLumileds power white LED performance



4


Lumileds Lumileds AlInGaP AlInGaP TechnologyTechnology

199119943x Improvement

199815x improvement

200122x improvement

Lumileds invests heavily to develop leading technology in LED material. OurAlInGaP technology leads the world in performance for Red, Orange, and Amber light. And we continue to improve performance.


(2001)

1000x1000um2

~ 17 x flux improvement

HP Indicator LED(1998)

300x400um2

LumiLeds Power LED(1999)

1000x1000um2

~ 10 x flux improvement

InGaNInGaN technology for Green, Blue, and Whitetechnology for Green, Blue, and White

5


0.001

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10

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1000

1960 1970 1980 1990 2000 2010

Year

Flux

/Pac

kage

(lum

ens)

Indicator LEDs

Luxeon TM

Haitz’s Haitz’s Law for LED FluxLaw for LED Flux•• LED Flux per package has doubled every 18LED Flux per package has doubled every 18--24 months for 30+ Years!!24 months for 30+ Years!!•• 19651965 Moore’sMoore’s Law “# of Transistors/chip will double every 18Law “# of Transistors/chip will double every 18--24 months!”24 months!”

LED TechnologyLED Technology


Die design Die design -- flipflip--chip submountchip submountA silicon submount is utilized for several reasons;A silicon submount is utilized for several reasons;

•• Silicon & sapphire have similar coefficients of thermal expansioSilicon & sapphire have similar coefficients of thermal expansion,n,•• Solder bumping of silicon wafers is an industry standard processSolder bumping of silicon wafers is an industry standard process,,•• A wide range of electronics can be integrated into silicon, A wide range of electronics can be integrated into silicon,

enabling a range of advanced products,enabling a range of advanced products,•• A hexagonal shape provides a compact optical element.A hexagonal shape provides a compact optical element.•• Extraction efficiency 2x higher than conventional GaN LEDsExtraction efficiency 2x higher than conventional GaN LEDs•• Power per LED ~1Power per LED ~1--2 orders of magnitude higher.2 orders of magnitude higher.

sapphire

GaN epiActive region

P-contact

N-contact

Si submount with patented ESD protection

Solder


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Die design Die design -- extraction efficiencyextraction efficiencyLight extraction efficiency is improved in flip chip designs by;Light extraction efficiency is improved in flip chip designs by;

•• No attenuation of light by semiNo attenuation of light by semi--transparent metal electrodes,transparent metal electrodes,•• Absorption of waveAbsorption of wave--guided light is dramatically reduced through guided light is dramatically reduced through

the use of highly reflective metallizations,the use of highly reflective metallizations,•• No light is obscured by bond pads or wires.No light is obscured by bond pads or wires.

30

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P-Contact Absorption (% per pass)

Extr

actio

n Ef

ficie

ncy

(%)

λ ~505nm

High reflectivity p-contact

Low reflectivity p-contact



WPE & WPE & εεee,colored LED,colored LED [[lm/Wlm/Wee] ]


Approximate State of the Art!

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ec)

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IQE & Extraction EfficiencyIQE & Extraction Efficiency



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Motivation for Luxeon highMotivation for Luxeon high--power LEDspower LEDs•• Direct Luxeon efficiency EXCEEDS the best available SaturatedDirect Luxeon efficiency EXCEEDS the best available Saturated light sources.light sources.

•• LongLong--Life Luxeon White Efficiency will EXCEED Important Conventional Life Luxeon White Efficiency will EXCEED Important Conventional White sourcesWhite sources

••Cost of flux is still above conventional sources.Cost of flux is still above conventional sources.

1

10

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1000

400 500 600 700 800 900


Lum

inous

Perfo

rman

ce(lu

mens

/Wat

t)

High PressureSodium (1kW)

Fluorescent (40W)Mercury Vapor (1kW)

Halogen (30W)

Tungsten (60W)

Red-FilteredTungsten (60W)

AlGaInP

AlGaInN AlGaAs

Eye Response Curve(CIE)

PCPC--WhiteWhite

Luxeon Luxeon LEDs in IlluminationLEDs in Illumination

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LuxeonLuxeon™™ approachapproachDie designDie design•• Large area die for high power capability,Large area die for high power capability,•• Electrode design for low spreading resistance,Electrode design for low spreading resistance,•• FlipFlip--chip configuration;chip configuration;

•• high extraction efficiency,high extraction efficiency,•• low thermal resistance,low thermal resistance,•• ability to integrate electronics.ability to integrate electronics.

Package designPackage design•• Low thermal resistance package,Low thermal resistance package,•• Stable, soft gel inner Stable, soft gel inner encapsulantencapsulant,,•• Controlled radiation pattern and efficient optics.Controlled radiation pattern and efficient optics.

System designSystem design•• Low thermal resistance board design,Low thermal resistance board design,•• Efficient secondary optical elements.Efficient secondary optical elements.



Luxeon High Power Package ExampleLuxeon High Power Package Example


Silicone Encapsulent

Cathode Lead InGaN Semiconductor Flip Chip

Plastic Lens

Heatsink Slug Silicon Sub-mount Chip with ESD Protection

Gold WireSolder Connection

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5mm Indicator Package Example5mm Indicator Package Example


Wedge Wire Bond

Lens (Diffuser)

LED Chip ConductiveEpoxy Die Attach; BallWire Bond Onto TopContact

Anode (+)Cathode (-)


0%

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0 2000 4000 6000 8000 10000 12000 14000Time (hrs)

Rel

ativ

e Li

ght O

utpu

t

L ighting Research Center - Sept 2002

Luxeon Luxeon -- Superior Lumen MaintenanceSuperior Lumen Maintenance

• Luxeon LEDs have superior lumen maintenance to epoxy encapsulated (5mm, surface mount, etc.) LEDs by design

• Ongoing tests show Luxeon is stable through 12,000 hours by which time 5mm LEDs have degraded ~80% and Incandescent bulbs have died

• Luxeon (colored and white) is expected to show an astounding 70%average lumen maintenance (30% degradation) at 50,000 hours

Incandescent (typical)

High–PowerLuxeon

5mm white LED

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Tower of Babble?Tower of Babble?

LED Technology & MetricsLED Technology & Metrics

optical power out / electric power in = Wall-Plug-Efficiency, WPE, (%,W/W)

photons out / electrons in = External Quantum Efficiency, EQE, %

photons internally generated / electrons in = Internal Quantum Efficiency , IQE, %

photons out / photons generated = extraction efficiency, %, ηext

photon energy / applied voltage (times electron charge) = electrical efficiency, %, ηv

lumens out / optical watt out = optical luminous efficacy, εo, [lm/Wo]

lumens out / electric power in = electrical luminous efficacy, εe, [lm/We]

WPE(%) = IQE*ηext*ηv

IQE*ηext = EQEEQE*ηv = WPE

WPE* εo = lm/We = εe


Tower of Babble take 2 for white LEDsTower of Babble take 2 for white LEDs


εo,ph = Luminous efficacy of phosphor/LED blend, [lm/Wo] ηQD = Quantum deficit in pumping phosphorηph = Phosphor quantum efficiencyηpkg = Package Efficiency - Catch all for color mixing penalty in RGB schemes,

phosphor re-absorption & added packaging loss due to addition of phosphor,...

εe,white [lm/We] = WPE(T,I) * εo,ph [lm/Wo] * ηQD * ηph(T) * ηpkg

IQE*ηext*ηv

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LED LED SkulduggerySkulduggery


1) Quoting EQE without Vf or WPE

2) Quoting low duty factor results

3) Quoting WPE without current or current density & total power out.

4) Quoting WPE without temperature

5) Quoting Cd without Flux

Paul’s Top 5 Sins What am I hiding?1) Vf, power efficiency

2) Thermal resistance, heating

3) GaN in particular has strong dependence of WPE on current not much light comes out of a device at very low currents!

4) WPE is strongly dependent on junction temperature forAlInGaP, less so for AlInGaN.

5) Radiation pattern




• Options for making white light from LEDs


•• Lumileds power white LED performanceLumileds power white LED performance



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Three methods of Generating LED White LightThree methods of Generating LED White Light•• Each method has potential strengths!Each method has potential strengths!

White Light from LEDsWhite Light from LEDs

RGB LEDs

Red + Green + Blue LEDs

470 525 590 630 (nm)

Blue Peak

Green Peak

Red Peak

Blue LED+

Yellow phosphor

Binary Complimentary

470 525 590 630 (nm)

Blue LEDSpectrum

Phosphor Emission

Combined Spectrum

UV LED + RGB Phosphor

UV LED + RGB phosphor

410 470 525 590 630 (nm)

UV LEDSpectrum

Phosphor Emission

Combined Spectrum


White from Blue LED + Phosphor(s)White from Blue LED + Phosphor(s)•• Advantages:Advantages:

•• Simple and single Yellow phosphor versions available today!Simple and single Yellow phosphor versions available today!•• Decent color rendering (Ra = 75 for Blue LED + Yellow Phosphor) Decent color rendering (Ra = 75 for Blue LED + Yellow Phosphor)

•• DisadvantagesDisadvantages•• Limits on efficiency due to Stokes shift, self absorption, tempeLimits on efficiency due to Stokes shift, self absorption, temperature effects…rature effects…•• Better color rendering (i.e. multi phosphor comes at cost of lumBetter color rendering (i.e. multi phosphor comes at cost of luminous efficiency!)inous efficiency!)

•• So how does this approach measure up using our OIDA metrics? (YASo how does this approach measure up using our OIDA metrics? (YAG + blue)G + blue)• Knowns: εo,ph [lm/Wo] ~ 330lm/Wo, ηηQD QD = 80%, ηph(25C) >95%

• For 150lm/W WPE(T,I) * ηηpkg pkg = 60% at appropriate temperature & drive!• For 200lm/W WPE(T,I) * ηηpkgpkg = 80% at appropriate temperature & drive!• Today’s production best is from Lumileds at ~10% :-)


εe,white [lm/We] = WPE(T) * εo,ph [lm/Wo] * ηQD * ηph(T) * ηpkg

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Today, PC LEDs are in the 20Today, PC LEDs are in the 20--30lm/W range!30lm/W range!•• TodaysTodays white LEDs are in the ~20white LEDs are in the ~20--30lm/W range!30lm/W range!

White from Blue LED + Phosphor(s)White from Blue LED + Phosphor(s)

010

203040506070

400 500 600 700 800nm

CCT=4000K, Ra=75

640

620630

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510

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10,000K

5000K

3300K2500K

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LED, T = 25C LED,T = 105C

YAG:CePlanckian locus

CIE1931

Ce3+ doped garnet family, e.g.(Y,Gd)3Al5O12

Combined with the same LED, Ce3+

phosphors hit the Planckian at different color temperatures:

Ra = 75 is not great (good FL has 83)but it is OK for some applications.

2626 Copyright (c) Copyright (c) Lumileds Lumileds Lighting LLC CompanyLighting LLC Company

The 2The 2--phosphorphosphor--converted LED converted LED –– 2pcLED2pcLED


490

480

470

460

500

510

520

530

540

590

600SrS:Eu

630620

640

TG:Eu

7118 7193

8206

61010,000K

5000K

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HP LED, T = 25CHP LED,T = 105CPlanckian locusPhosphorsCIE1931Series15

combospec

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0.50

1.00

1.50

2.00

400 500 600 700 800

Ra = 92

combospec

0.000.200.400.600.801.001.201.401.60

400 500 600 700 800

Ra = 92

1 LED + 2 phosphors Adding green and red to the blue of the LED opens a huge color gamut and allows for de-luxe white of any color temperature – one option:• SrGa2S4:Eu2+ - green• SrS:Eu2+ - red

The dipole-allowed 5d-4f transitions of Ce3+ and Eu2+

are uniquely suited for color converters: high absorption, small Stoke’s shift

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Progress on Temperature stability of PhosphorsProgress on Temperature stability of Phosphors


0

200000

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600000

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1000000

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25

50100

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200novel phosphors with improved color specs emerge; in this case using a Ce3+ - Pr3+ transfer of excitation energy and yielding more temperature stable behavior

(Y,Gd)AG, 4 mol% Ce

0

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Temperature, C

I(T)/I

(25C

), %

[Gd]0%

25

5075

measured on powders (Y,Gd)AG:Ce

0

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radi

ance

und

er 4

60 n

m e

xcita

tion

25 C50100120150200


White from UV LED + RGB PhosphorsWhite from UV LED + RGB Phosphors•• Advantages:Advantages:

• White point determined by phosphors ONLY! (i.e. tolerant to LED variation)• Excellent color rendering possible!• Superficially “Simple to manufacture!” Reality is not so simple!• Temperature stability of phosphors. (Can be great!)

•• DisadvantagesDisadvantages• Potential for damaging UV light leakage. • Limits on efficiency due to Stokes shift, self absorption, temperature effects,…

•• So how does this approach measure up using our OIDA metrics? (UVSo how does this approach measure up using our OIDA metrics? (UV + RGB)+ RGB)• Knowns: εo,ph [lm/Wo] <300lm/Wo, ηηQDQD = 70%(380nm), ηph(25C) >95% (guess?)

• For 150lm/W WPE(T,I) * ηηpkg pkg = 75% at appropriate temperature & drive!• For 200lm/W WPE(T,I) * ηηpkgpkg = 100% at appropriate temperature & drive!



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UV LED must be >2x Green LED WPE for same lm/W!UV LED must be >2x Green LED WPE for same lm/W!•• Downshift in color causes fundamental energy loss.Downshift in color causes fundamental energy loss.

•• Scattering in phosphor + absorption in package (inc. phosphor) rScattering in phosphor + absorption in package (inc. phosphor) reduces extraction educes extraction efficiency! Today’s best package efficiency is ~50% for Blue +efficiency! Today’s best package efficiency is ~50% for Blue + Yellow phosphor, Yellow phosphor, UV + RGB phosphor likely to be even worse!UV + RGB phosphor likely to be even worse!

UV LED pumped RGB PhosphorsUV LED pumped RGB Phosphors

0%

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100%

370 380 390 400 410 420 430UV Pump Wavelength (nm)

Pow

er C

onve

rsio

n (%

)

Red 630nmBlue 460nmGreen 540nmWhite White + PkgAssuming 50% pkg. Efficiency!


White from RGB LEDsWhite from RGB LEDs•• Advantages:Advantages:

• Long term likely the most efficient!• Excellent color rendering possible! (There is a price thou• Very large color Gamut available!• Dynamic tuning & monitoring of color point possible!

•• DisadvantagesDisadvantages• Temperature stability of LEDs varies with color.• Dynamic tuning & monitoring of color point required?!

•• So how does this approach measure up using our OIDA metrics? (UVSo how does this approach measure up using our OIDA metrics? (UV + RGB)+ RGB)• Knowns: εo,RGB [lm/Wo] ~300lm/Wo, ηηQDQD = 100%, ηph(25C) = 100%

• For 150lm/W WPE(T,I) * ηηpkg pkg = 50% at appropriate temperature & drive!• For 200lm/W WPE(T,I) * ηηpkgpkg = 67% at appropriate temperature & drive!



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WPE & WPE & εεee,colored LED,colored LED [[lm/Wlm/Wee] ]



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(%)


IQE & Extraction EfficiencyIQE & Extraction Efficiency



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Performance characteristics Performance characteristics

0 50 100 150 200

4

8

12

16

20 InGaN LEDsλ

d ~530 nm

"5 mm" LED

Power LED

Exte

rnal

Qua

ntum

Eff

icie

ncy

(%)

Current Density (A/cm2)

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120 InGaN LEDsλ

d ~530 nm

"5 mm" LED

Power LED

Current Density (A/cm2)

Lum

inou

s Fl

ux (

lm)

Typical InGaN EQE vs. CurrentTypical InGaN EQE vs. Current


AlInGaP Red lm/W & IQE Temperature DependenceAlInGaP Red lm/W & IQE Temperature Dependence


Approximate State of the Art!T0 = 173C Photometrically

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en/W

elec

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~IQ

E (%

)

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Three methods of Generating LED White LightThree methods of Generating LED White Light•• Each method has potential strengths!Each method has potential strengths!


RGB LEDs

Red + Green + Blue LEDs

470 525 590 630 (nm)

Blue Peak

Green Peak

Red Peak

Blue LED+

Yellow phosphor

Binary Complimentary

470 525 590 630 (nm)

Blue LEDSpectrum

Phosphor Emission

Combined Spectrum

UV LED + RGB Phosphor

UV LED + RGB phosphor

410 470 525 590 630 (nm)

UV LEDSpectrum

Phosphor Emission

Combined Spectrum


OptoOpto--electronics Industry Assoc.electronics Industry Assoc.

OIDA 2002 2005 2007 2010 2012 2020Efficiency (lm/W) 30 75 150 200Cost ($/klm) 100 10 5 2Lifetime (khrs) 20 20 100 100CRI 75 80 85 85

21st Century Lighting (lm/W) 60 120

White Technology 2002 2005 2007 2010 2012 2020Efficiency (lm/W) 30 60 75 120 150 200RGB White 10% 20% 25% 40% 50% 67%Blue + Phosphor(s) White 12% 24% 30% 48% 60% 80%UV + 3 Phosphor White 15% 30% 38% 60% 75% 100%

Required LED Pump WPE(T,I) * ηpkg

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And the efficiency winner is?And the efficiency winner is?•• UV + RGB phosphors IFUV + RGB phosphors IF

•• UV LED is fundamentally ~2x higher WPE than green LED?UV LED is fundamentally ~2x higher WPE than green LED?•• And RGB phosphors with high efficiency at high temperature can bAnd RGB phosphors with high efficiency at high temperature can be found?e found?

•• Blue + Yellow phosphor IFBlue + Yellow phosphor IF•• Blue LED is fundamentally ~1.5x higher WPE than green LED?Blue LED is fundamentally ~1.5x higher WPE than green LED?•• And phosphor with Ra > 85 & high efficiency at high T can be fouAnd phosphor with Ra > 85 & high efficiency at high T can be found?nd?

•• Red, Green and Blue LED IFRed, Green and Blue LED IF•• AlInGaP T0 can be raised or other Red semiconductor can be masteAlInGaP T0 can be raised or other Red semiconductor can be mastered?red?•• Will Will InN InN ever make efficient Red?ever make efficient Red?


Anyone going to Vegas?





• Competition in the market for Illumination Sources Incandescent & Fluorescent Bulbs.

•• LumiledsLumileds power white LED performancepower white LED performance



20


How Much Energy is Used for LightingHow Much Energy is Used for Lighting•• In 1999 the US used 3 Trillion In 1999 the US used 3 Trillion kWhr kWhr of Electricity!of Electricity!

•• 20% or 600 Billion 20% or 600 Billion kWhr kWhr of of Electicity Electicity generated was used in Lighting!generated was used in Lighting!

•• Incandescent/Hal. lamps burn 40% of electricity to produce 15% oIncandescent/Hal. lamps burn 40% of electricity to produce 15% of light!f light!

•• Fluorescent/HID lamps use 60% of electricity to produce 85% of lFluorescent/HID lamps use 60% of electricity to produce 85% of light!ight!

•• Illumination market is $60Billion/yr and growing slowly, ~2%/yrIllumination market is $60Billion/yr and growing slowly, ~2%/yr

Illumination MarketsIllumination Markets


Incandescent BulbsIncandescent Bulbs•• Incandescent = hot light, emitted from a (tungsten) filament at Incandescent = hot light, emitted from a (tungsten) filament at around 2800around 2800ooKK

•• Disadvantages:Disadvantages:•• mostly inframostly infra--redred•• glass vacuum envelope & filament both break easilyglass vacuum envelope & filament both break easily•• <15 lm/W luminous (<5% power) efficiency<15 lm/W luminous (<5% power) efficiency•• fire hazard, burnt fingers, maintenancefire hazard, burnt fingers, maintenance

•• Advantages:Advantages:•• Radiant coolingRadiant cooling•• Cheap 0.0005$/lumenCheap 0.0005$/lumen•• klm klm per package!per package!


Basic disadvantage: Lots of heat ANDno chance to come close to DAYLIGHT = 6500oK

black body spectra

00.20.4

0.60.8

11.21.4

1.61.8

2

0.3 0.4 0.5 0.6 0.7 0.8 0.9

pow

er s

pect

ra, n

orm

.@60

0 nm 3000K

4000

5500

6500

7500

µmCourtesy Gerd Mueller LL

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Fluorescent BulbsFluorescent Bulbs•• Fluorescent = cold light, emitted by phosphors excited by gas diFluorescent = cold light, emitted by phosphors excited by gas discharge.scharge.

•• Advantages:Advantages:•• High efficiency 80+lm/W & High Flux High efficiency 80+lm/W & High Flux klmklm/lamp/lamp•• Moderate cost for large lamps 0.002$/lmModerate cost for large lamps 0.002$/lm

•• Disadvantages:Disadvantages:•• Lifetime short <10,000 hrs resulting in high maintenance.Lifetime short <10,000 hrs resulting in high maintenance.•• Glass vacuum envelope leaks/breaks, ballast noisy.Glass vacuum envelope leaks/breaks, ballast noisy.•• Mercury!!Mercury!!


Basic Advantage: any color temperature possible by tri-color mixing

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rad.

flux

, a.u

.

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flux

, a.u

.black body 3600 K

fluorescent, CCT=3600 K

Ra = 83

Courtesy Gerd Mueller LL


White LED technologies share White LED technologies share Four Four challenges!challenges!* Maximize efficiency - lm/W

* Color Control: CCT, Ra

* Maximize flux density - lm/package

* Increase the Flux per Buck - kLm/$

15 W110 lm/bulb7 lm/WIncandescent

4 W145 lm/bulb36 lm/WFluorescent

45 W475 lm/bulb10 lm/WIncandescent

20W320 lm/bulb

17 lm/WHalogen

Common Low Wattage Bulbs Common Low Wattage Bulbs

22



lamp watts Life initial Maintained price Efficacy klm/$ cost of lighthours lumens lumens $$$ lm/W $/MLH

60A - Incandescent bulb 60 1000 750 750 0.34 12.5 2.2059 8.010$

15SLS - Compact Fluorescent 15 10000 900 765 14.97 51.0 0.0511 1.964$

F34CWE - Fluorescent Tube 34 20000 2600 2350 1.5 69.1 1.5667 1.447$ F32T8ADV - Fluorescent Tube 32 24000 3100 2950 1.5 92.2 1.9667 1.085$

MH400 - Metal Halide 400 20000 36000 24000 54 60.0 0.4444 1.667$

Luxeon 5.138 50000 120 90 10 17.5 0.0090 5.713$

Cost of Light ($/Million Lumen Hours)Cost of Light ($/Million Lumen Hours)

$/MLH = 10/q(((p+h)/L)+w*r)q = mean lamp lumen w = wattagep = Lamp cost in cents r = energy cost $0.01/kwhrh = Labor cost in cents Lamp data Courtesy Bill Ryan – Philips Lighting

* = Luxeon Life defined as 50% initial brightnessStandard lamp Life defined as 50% dead

*


Potential Power Savings vs. Traditional LightingPotential Power Savings vs. Traditional Lighting•• TodaysTodays white LEDs are in the ~30lm/W range, but still low flux, 120lm white LEDs are in the ~30lm/W range, but still low flux, 120lm max!max!

•• Assume 50% optical efficiency for CFL & Fluorescent!Assume 50% optical efficiency for CFL & Fluorescent!


0

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Po

wer

Sav

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)

Incandescent

Halogen

CFL

Fluorescent

Luxeon 2002

OIDA 2007

OIDA 2012

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So Where to High Power So Where to High Power LEDsLEDs fit?fit?• Customers are willing to pay for high quality white light.•• Today:Today:

• LEDs have higher “cost of light” than Fluorescent but lower than incandescent.• LEDs have higher “quality light” than Fluorescent but lower than incandescent.• LEDs dominate applications requiring saturated color.

•• Tomorrow:Tomorrow:• LEDs “cost of light” will match Fluorescent in ~4-6years.• LEDs “quality of light” can be adjusted at price of decreasing efficiency.

•• LEDsLEDs offer “Never before possible!” opportunities to control the ligoffer “Never before possible!” opportunities to control the lighting hting environment: RGB control; Vibration immunity, long life, many tenvironment: RGB control; Vibration immunity, long life, many times imes longer than the fixture, automobile,…; Styling design; No Mercurlonger than the fixture, automobile,…; Styling design; No Mercury;...y;...

•• Conclusion: Near term LEDs must dominate Saturated Color marketConclusion: Near term LEDs must dominate Saturated Color markets AND s AND must penetrate White Illumination Markets through niches!must penetrate White Illumination Markets through niches!






• Lumileds power white LED performance



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Lumileds 100 lumen Club!Lumileds 100 lumen Club!•• These are the only LEDs that approach “Illumination” flux!These are the only LEDs that approach “Illumination” flux!

•• A 15W Incandescent bulb is A 15W Incandescent bulb is ONLYONLY ~110lm of undirected white light!~110lm of undirected white light!


Power (W/LED) lm/LED DemonstratedRed 2.5 105 February-01Amber 1.9 110 December-99Green 2.5 108 March-01White 6.5 100.2 July-01White 5.0 150 October-01


What about Radiometric Power?!What about Radiometric Power?!•• State of the art 400nm indicator LEDs provide 15mW of power. State of the art 400nm indicator LEDs provide 15mW of power.

•• How much power can a Luxeon part generate? :How much power can a Luxeon part generate? :--) (Best demonstration)) (Best demonstration)

High Power Deep Blue LEDsHigh Power Deep Blue LEDs

If (mA) W/LED WPE DateDeep Blue 430nm 1400 1.2 24% August-01

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Lumileds LuxeonLumileds LuxeonTMTM Series D Prototype White LEDSeries D Prototype White LED•• Single Series D Luxeon White LED can produce 35% Single Series D Luxeon White LED can produce 35% MORE LIGHTMORE LIGHT while using while using

60% 60% LESS ENERGY LESS ENERGY compared to 15W incandescent compared to 15W incandescent lightbulblightbulb!!


150 lm/bulb30 lm/W


Lumileds LuxeonLumileds LuxeonTMTM RingRing•• Fixture design by Philips Lighting and Lumileds.Fixture design by Philips Lighting and Lumileds.

•• 12 12 Luxeon’sLuxeon’s, ~240 lumens. Ring available , ~240 lumens. Ring available Now!Now!


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Selling points in niches for high power LEDsSelling points in niches for high power LEDs•• Battery operated flashlights: Battery operated flashlights: (lm/W, optical efficiency, lm/mm^2)(lm/W, optical efficiency, lm/mm^2)

•• MiniMini--accent lights: accent lights: (lm/W, color control, color uniformity, lifetime)(lm/W, color control, color uniformity, lifetime)

•• Automotive white lights: Automotive white lights: (lm/mm^2, beam control, lifetime)(lm/mm^2, beam control, lifetime)

•• Security lighting:Security lighting: ((lmWlmW, lifetime), lifetime)

•• Monitor/TV backlights:Monitor/TV backlights: (Color control, lm/W, No Mercury, color gamut)(Color control, lm/W, No Mercury, color gamut)

•• Path/Stair lighting:Path/Stair lighting: (lm/W, lifetime, rugged (lm/W, lifetime, rugged contructioncontruction))

•• Commercial Display lighting:Commercial Display lighting: (lm/W, cool light w/ little heat, lifetime)(lm/W, cool light w/ little heat, lifetime)




Is 100x Reduction in Cost Realistic?Is 100x Reduction in Cost Realistic?•• Recall: LED lamps will be far more expensive than incandescent,Recall: LED lamps will be far more expensive than incandescent, halogen halogen

or fluorescent lamps for about a decade.or fluorescent lamps for about a decade.• 60W, 1000lm incandescent bulb from Home Depot, $0.25 = $0.00025/lm• Lumileds 125lm 5W LED, $10.00 = $0.08/lm ~300x higher initial cost

•• Increase in current density & operating temperature 3x Increase in current density & operating temperature 3x -- 5x, 25x, 2--4 years.4 years.•• Increase in white efficiency: Per OIDA 5x, 10 years.Increase in white efficiency: Per OIDA 5x, 10 years.•• Decrease in cost 15Decrease in cost 15--20% / year: 4x, 620% / year: 4x, 6--10 years10 years•• Lighting fixture efficiency: 2Lighting fixture efficiency: 2--4x available now.4x available now.

Conclusion!Conclusion!

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Conclusion!Conclusion!Fast forward: 25 years

What’s a lightbulb and why wouldanyone want to change one?

Change the “Lightbulb”


“Perhaps we may scare away the ghost of so many years ago with a little

Luxeon MR16 - 150lm (30lm/W)

paul s. martin - 12feb03 ieee santa clara final for...

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