CIE深入探讨

Copyright©2011,ULICopyright©2011,ULIQuestions•Whatarelm(flux),cd,nits,lux,efficacyandmW?•Whatarespectrum,wdandwp•Whatarergb,xy,uvandu’v’?•WhatarethedefinitionofCTandCCT?•Whatisduv?•WhatisMcAdamStep?•WhatisCRI?•WhatareSolidStateLightingandLEDLighting?•Duvoftenmissing•CCTandCRIdonottellthewholestoryofcolorqualityLightingFactsLabelCopyright©2011,ULIHumanEyeStructure1.Rodsareusedprimarilytoseeatlowlevelsoflight,whileconesareusedtodeterminecolor,depth,andintensity.2.Thefoveacompriseslessthan1%ofretinalsizebuttakesupover50%ofthevisualcortexinthebrain.3.Thecentreofthefoveaisthefoveola-about0.2mmindiameter-whereonlyconephotoreceptorsarepresentandtherearevirtuallynorods.Copyright©2011,ULICopyright©2011,ULISIPhotometryUnitsQuantitySymbolSIunitAbbr.NotesRadiantFluxWwattradiantenergyperunittimeLuminousFlux(光通量)ForΦLumenlmluminouspowerinLumenIntensity(光度)Ivcandela(=lm/sr)cdFluxemittingfromasteradian(sr)Luminance(輝度)Lvnits(cd/m2)IntensityemittingfromaunitsurfaceIlluminance(照度)Evlux(=lm/m2)lxFluxincidentonaunitsurfaceRadianceRvW/sr/m2ratioofradiantfluxtoEfficacy(光效)ηlm/Wratiooffluxtopowerconsumed•Photopicluminosityfunction：bestapproximatestheresponseofthehumaneyeforeverydaylightlevelandalsousedintheCIE1931colorspace,•Scotopicluminosityfunction：forlowlightlevels•Theluminousflux(orvisibleenergy)inalightsourceisdefinedbythephotopicluminosityfunction.Thefollowingequationcalculatesthetotalluminousfluxinasourceoflight.whereFistheluminousfluxinlumens,isthepowerspectraldensityoftheradiation,inwattsperunitWL.(alsoknownas)isthestandardluminosityfunction(whichisdimensionless).Copyright©2011,ULILuminosity(Vision)functionCopyright©2011,ULI顏色視覺理論(ColorVisionTheory)•牛頓(1642-1727)推翻希臘古典模式-白與黑為色彩的基本原色，利用三棱鏡與透鏡進行分光實驗將色與光之研究整理成光學一書。將白光分解為七色光,將七色光聚集後還原為白光並建立色相環(huecircle)成為色彩科學理論的基礎研究•TrichromaticTheory(Young–Helmholtztheory):Proposedinthe19thcenturybyThomasYoungandHermannvonHelmholtz,statesthattheretina'sthreetypesofconesarepreferentiallysensitivetoblue,green,andred.•OpponentProcessTheory:ProposedbyEwaldHeringin1872.Itstatesthatthevisualsysteminterpretscolorinanantagonisticway:redvs.green,bluevs.yellow,blackvs.white.『人眼內含有三種感受紅−綠(R−G)，黃−藍(Y−B)，白−黑(W−K)色彩的受光器，色覺是由各受光器對光產生的反應』Cone(錐)andRod(桿)CellsinHumanEyesConetypeNameRangePeakwavelengthSβ400–500nm420–440nmMγ450–630nm534–555nmLρ500–700nm564–580nmWhatisCIE?CIE:CommissionInternationaledeL‘Eclairage(法)InternationalCommissiononIllumination(英)國際照明委員會(中)是一個有關光、照明、顏色和色度空間科學領域的國際權威組織。總部位於奧地利維也納。CIEisanindependent,non-profitorganizationthatservesmembercountriesonavoluntarybasis.ItisrecognizedbyISOasaninternationalstandardizationbody.CIE19312°StandardObserverduetothebeliefthatthecolor-sensitiveconesresidedwithina2°arcofthefovea,andisdiscretizedat5nmwavelengthintervalsCIE196410°StandardObserverobserverswereinstructedtoignorethecentral2°spot.但由於人們長期使用的習慣使然，迄今CIE1931色度圖仍然是LEDIndustry使用最廣泛的標準。Copyright©2011,ULI•3原色(單波長)：•R=700.0nmG=546.1nmB=435.8nm•1.0000:4.5907:0.0601(forsourceluminance)•72.0962:1.3791:1.0000(forsourceradiantpower)色彩量化國際照明委員會(CIE)於1931年根據以下的基準制定了標準配色函數(ColorMatchingFunctions)。Copyright©2011,ULICIERGBColorSpaceTheCIE1931RGBColorMatchingFunctionsCopyright©2011,ULICIEXYZColorMatchingFunctionCopyright©2011,ULICopyright©2011,ULIxy(1931)-uv(1960)-u’v’(1976)•CIE1960u=4x/(12y−2x+3)v=6y/(12y−2x+3)•CIE1976u'=uv'=3/2v0.000.100.200.300.400.500.600.700.800.900.000.100.200.300.400.500.600.700.80x,u,u'y,v,v'uvxyu'v'x=3u/(2u−8v+4)y=2v/(2u−8v+4)Copyright©2011,ULIColorTemperature(CT)andCorrelatedCTCopyright©2011,ULICCTisvalidwithindistance0.05fromthePlanckianlocusonthe(u’,2/3·v’)diagram.(CIE15:2004)Temperature[K]ofaPlanckianradiatorwhosechromaticityisclosesttothatofagivenstimulusontheCIE(u’,2/3v’)coordinate.(CIE15:2004)DefinitionofCCTCopyright©2011,ULIDefinition:ClosestdistancefromthePlanckianlocusonthe(u',2/3v')diagram,with+signforaboveand-signforbelowthePlanckianlocus.(ANSIC78.377-2008)Symbol:Duv•CCTandDuvcanspecifythechromaticityoflightsourcesjustlike(x,y).•Thetwonumbers(CCT,Duv)providescolorinformationintuitively.(x,y)doesnot.•DuvneedstobedefinedbyCIEDefinitionDuvCopyright©2011,ULIComputationofCCTCopyright©2011,ULIRobertson'sAlgorithmCCTApproximation•McCamyproposedcubicapproximation(1992)CCT(x,y)=−449n3+3525n2−6823.3n+5520.33,wheren=(x−xe)/(y−ye)and(xe=0.3320,ye=0.1858)-epicenter;(2000~12500K)•Hernández-Andrés’sexponentialform(1999)CCT(x,y)=A0+A1exp(−n/t1)+A2exp(−n/t2)+A3exp(−n/t3)3000~50000K50000~800000Kxe0.33660.3356ye0.17350.1691A0-949.8631536284.48953A16253.803380.00228t10.921590.07861A228.705995.4535×10-36t20.200390.01543A30.00004t30.07125Copyright©2011,ULISimpleCalculationfromx,yoru’,v’toDuvCopyright©2011,ULIConversionfrom(CCT,Duv)backto(x,y)Copyright©2011,ULISimpleCCTcalculationfrom(x,y)or(u’,v’)to(CCT,Duv)Copyright©2011,ULIMacAdam’s25Ellipses•Atafixedluminance~48cd/m2,oneofthecolors(thetestcolor)wasfixed,buttheotherwasadjustablebytheobserver,andtheobserverwasaskedtoadjustthatcoloruntilitmatchedthetestcolor.•thecolormatchesmadebytheobserverfellintoanellipseontheCIE1931chromaticitydiagram.•25p