Kev tsom xam ntawm cov txheej txheem tseem ceeb rau cov LEDs dawb rau teeb pom kev zoo
Dawb LED hom: Cov txheej txheem tseem ceeb rau cov LEDs dawb rau teeb pom kev zoo yog: 1 xiav LED + phosphor hom; 2 RGB LED hom; 3 ultraviolet LED + phosphor hom
1. Blue-LED nti + daj-ntsuab phosphor hom muaj xws li ntau xim phosphor derivative
Cov xim daj-ntsuab phosphor txheej absorbs ib feem ntawm lub teeb xiav ntawm LED nti los tsim photoluminescence, thiab lwm qhov ntawm lub teeb xiav los ntawm LED nti xa cov phosphor txheej thiab converges nrog lub teeb daj-ntsuab tawm los ntawm phosphor ntawm ntau lub ntsiab lus nyob rau hauv qhov chaw, thiab lub teeb liab, ntsuab thiab xiav sib xyaw ua kom pom lub teeb dawb; Nyob rau hauv no txoj kev, lub siab tshaj plaws theoretical tus nqi ntawm lub photoluminescence conversion efficiency ntawm ib qho ntawm sab nraud quantum efficiency yuav tsis ntau tshaj 75%; thiab tus nqi rho tawm ntawm cov nti luminescence tsuas tuaj yeem ncav cuag li 70%, yog li theoretically, lub teeb xiav yog dawb. LED teeb pom kev zoo yuav tsis tshaj 340 Lm / W, CREE mus txog 303Lm / W hauv xyoo dhau los, thiab nws tsim nyog ua kev zoo siab yog tias qhov ntsuas tau raug.
2, Liab, ntsuab thiab xiav peb thawj xim ua ke RGB LED hom xws li RGBW-LED hom, thiab lwm yam.
R-LED (liab) + G-LED (ntsuab) + B- LED (xiav) Peb lub LEDs sib xyaw ua ke, thiab lub teeb liab, ntsuab thiab xiav ntawm peb lub ntsiab xim yog sib xyaw ncaj qha rau hauv qhov chaw los ua lub teeb dawb. Txhawm rau tsim cov teeb pom kev zoo siab dawb hauv txoj kev no, ua ntej ntawm tag nrho cov, LEDs ntawm ntau xim, tshwj xeeb tshaj yog cov LEDs ntsuab, yuav tsum yog cov teeb pom kev zoo, uas yog kwv yees li 69% pom los ntawm "lub zog dawb lub teeb".Tam sim no, Kev ua tau zoo ntawm xiav thiab liab LEDs tau siab heev, thiab kev ua haujlwm hauv quantum yog tshaj 90% thiab 95%, feem, tab sis sab hauv quantum efficiency ntawm ntsuab LEDs yog nyob deb tom qab. Qhov tshwm sim uas GaN-raws li LED lub teeb ntsuab tsis zoo yog hu ua "qhov sib txawv ntawm lub teeb ntsuab." Qhov laj thawj tseem ceeb yog qhov ntsuab LED tsis pom nws tus kheej cov khoom siv epitaxial. Cov ntaub ntawv phosphorous-arsenic nitride uas twb muaj lawm muaj kev ua haujlwm tsawg hauv cov xim daj-ntsuab spectrum, thiab lub teeb liab lossis xiav lub teeb epitaxial cov khoom siv los ua cov LED ntsuab. Ntawm cov xwm txheej tam sim no qis dua, cov LEDs ntsuab muaj qhov ua kom pom kev zoo dua li xiav + phosphor ntsuab lub teeb vim tsis muaj phosphor hloov pauv. Nws tau tshaj tawm tias qhov kev ua haujlwm luminous nce mus txog 291 Lm / W ntawm 1 mA.Txawm li cas los xij, lub teeb pom kev zoo ntawm lub teeb ntsuab tshwm sim los ntawm cov nyhuv Droop tau txo qis heev ntawm qhov tam sim no loj, thiab thaum qhov ceev tam sim no tau nce, lub teeb pom kev zoo. ceev ceev. Ntawm qhov tam sim no ntawm 350 mA, luminous efficiency yog 108 Lm / W, thiab nyob rau hauv cov xwm txheej ntawm 1 A, lub luminous efficiency poob mus rau 66 Lm / W.
Rau pab pawg III phosphides, emitting lub teeb rau ntsuab band ua ib qho tseem ceeb barrier rau cov khoom siv system. Hloov cov muaj pes tsawg leeg ntawm AlInGaP ua rau nws ci ntsuab es tsis txhob liab, txiv kab ntxwv los yog daj - ua rau cov cab kuj tsis txaus vim qhov sib txawv ntawm cov khoom siv hluav taws xob tsawg, tshem tawm cov khoom siv hluav taws xob zoo.
Hauv qhov sib piv, Pab Pawg III nitrides nyuaj dua kom ua tiav, tab sis qhov nyuaj tsis tuaj yeem dhau mus. Nrog rau qhov system no, ob yam uas ua rau kev ua tau zoo txo qis vim qhov txuas ntxiv ntawm lub teeb rau hauv cov kab ntsuab yog: sab nraud quantum efficiency thiab hluav taws xob tsis zoo. Qhov txo qis hauv quantum efficiency sab nraud tshwm sim los ntawm qhov tseeb tias lub teeb ntsuab LED muaj lub siab rau pem hauv ntej voltage ntawm GaN, uas ua rau lub zog hloov pauv tus nqi txo. Qhov thib ob qhov tsis zoo yog qhov ntsuab LED txo qis thaum txhaj tshuaj tam sim no ceev, uas yog daig los ntawm cov nyhuv droop. Cov nyhuv Droop kuj tshwm sim nyob rau hauv xiav LEDs, tab sis nws tseem ceeb dua nyob rau hauv ntsuab LEDs, uas ua rau txo qis kev khiav hauj lwm tam sim no. Txawm li cas los xij, muaj ntau qhov laj thawj rau qhov ua rau cov nyhuv droop, tsis yog tsuas yog Auger compound, tab sis kuj yog qhov chaw tsis raug, cov cab kuj dhau los yog electron to. Cov tom kawg yog kho kom zoo dua los ntawm high voltage internal electric teb.
Yog li ntawd, txoj hauv kev los txhim kho luminous efficiency ntawm ntsuab LEDs: ntawm ib sab, yuav ua li cas txo cov nyhuv Droop nyob rau hauv cov ntaub ntawv epitaxial uas twb muaj lawm los txhim kho lub teeb efficiency; Qhov thib ob nam, lub photoluminescence hloov dua siab tshiab ntawm xiav LED ntxiv rau ntsuab phosphor emits ntsuab lub teeb, txoj kev yuav tau txais high-efficiency ntsuab teeb, thiab theoretically muaj peev xwm ua tau siab tshaj qhov tam sim no dawb lub teeb nyhuv, uas belongs rau tsis-spontaneous ntsuab teeb, thiab cov xim purity tshwm sim los ntawm spectral broading txo, uas yog unfavorable rau zaub, tab sis rau dog dig Tsis muaj teeb meem nrog illumination. Lub teeb ntsuab tau txais los ntawm txoj kev no muaj peev xwm ntau dua 340 Lm / W, tab sis nws tseem tsis tshaj 340 Lm / W tom qab sib txuas lub teeb dawb. Thib peb, txuas ntxiv mus tshawb fawb thiab nrhiav nws tus kheej cov khoom siv epitaxial, tsuas yog nyob rau hauv txoj kev no, muaj kev cia siab tias los ntawm kev tau txais lub teeb ntsuab ntau dua 340 Lm / w, lub teeb dawb ua ke los ntawm liab, ntsuab thiab xiav peb lub teeb xim thawj LEDs yuav yog siab tshaj lub teeb efficiency txwv ntawm xiav nti hom dawb LED 340 Lm / W.
3.UV LED nti + peb thawj xim phosphor teeb
Lub ntsiab tsis xws luag ntawm saum toj no ob lub LEDs dawb yog qhov tsis sib xws spatial faib ntawm luminosity thiab chromaticity. Lub teeb ultraviolet tsis pom rau tib neeg lub qhov muag. Yog li ntawd, tom qab lub teeb ultraviolet tawm ntawm lub nti, nws yog absorbed los ntawm peb lub ntsiab xim phosphors ntawm txheej encapsulating, thiab photoluminescence ntawm phosphor hloov mus rau hauv lub teeb dawb, uas yog ces emissions mus rau hauv qhov chaw. Qhov no yog nws qhov txiaj ntsig loj tshaj plaws, ib yam li cov teeb fluorescent tsoos, nws tsis muaj xim tsis sib xws. Txawm li cas los xij, qhov theoretical teeb pom kev zoo ntawm ultraviolet nti hom dawb LED tsis tuaj yeem siab dua qhov theoretical tus nqi ntawm xiav nti hom lub teeb dawb, thiab nws tsis tshua muaj siab dua li qhov theoretical tus nqi ntawm RGB hom dawb lub teeb. Txawm li cas los xij, nws tsuas yog los ntawm kev txhim kho kev ua haujlwm siab trichromatic phosphors haum rau ultraviolet lub teeb excitation uas nws muaj peev xwm tau txais ultraviolet lub teeb-hom dawb LEDs uas nyob ze los yog txawm ntau npaum li cas tam sim no ob lub LEDs dawb. Qhov ze dua rau lub teeb xiav-lub teeb ultraviolet LEDs, qhov ua tau Qhov loj dua qhov nruab nrab-yoj thiab luv-yoj ultraviolet hom dawb LEDs yog, qhov tsis yooj yim dua.