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Area Lighting / Colorimetry

IEV ref 845-23-076

en
CIE 1976 L*a*b* colour space
CIELAB colour space
three-dimensional, approximately uniform colour space produced by plotting in rectangular coordinates L*, a*, b*, quantities defined by the equations:
  • L*=116f( Y/ Y n )16 a*=500[ f( X/ X n )f( Y/ Y n )] b*=200[ f( Y/ Y n )f( Z/ Z n )] MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqipu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGacaGaaiaabmqaamaabaabaaGceaqabeaacaWGmb GaaiOkaiabg2da9iaaigdacaaIXaGaaGOnaiaadAgadaqadaqaamaa lyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGcca GLOaGaayzkaaGaeyOeI0IaaGymaiaaiAdaaeaacaWGHbGaaiOkaiab g2da9iaaiwdacaaIWaGaaGimamaadmaabaGaamOzamaabmaabaWaaS GbaeaacaWGybaabaGaamiwamaaBaaaleaacaqGUbaabeaaaaaakiaa wIcacaGLPaaacqGHsislcaWGMbWaaeWaaeaadaWcgaqaaiaadMfaae aacaWGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaaaGa ay5waiaaw2faaaqaaiaadkgacaGGQaGaeyypa0JaaGOmaiaaicdaca aIWaWaamWaaeaacaWGMbWaaeWaaeaadaWcgaqaaiaadMfaaeaacaWG zbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaaiabgkHiTi aadAgadaqadaqaamaalyaabaGaamOwaaqaaiaadQfadaWgaaWcbaGa aeOBaaqabaaaaaGccaGLOaGaayzkaaaacaGLBbGaayzxaaaaaaa@6779@

where

  • f( X/ X n )= ( X/ X n ) 1/3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaadMfaaeaaca WGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaamaaCaaa leqabaGaaGymaiaac+cacaaIZaaaaaaa@429E@ if ( X/ X n )> ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGH+aGpdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@3FA3@
  • f( X/ X n )=( 841/ 108 )( X/ X n )+4/ 29 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaaiIdacaaI0a GaaGymaaqaaiaaigdacaaIWaGaaGioaaaaaiaawIcacaGLPaaadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaey4kaSYaaSGbaeaacaaI0aaabaGaaGOm aiaaiMdaaaaaaa@498C@ if ( X/ X n ) ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGHKjYOdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@4050@

and

  • f( Y/ Y n )= ( Y/ Y n ) 1/3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaadMfaaeaaca WGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaamaaCaaa leqabaGaaGymaiaac+cacaaIZaaaaaaa@429E@ if ( Y/ Y n )> ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGH+aGpdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@3FA3@
  • f( Y/ Y n )=( 841/ 108 )( Y/ Y n )+4/ 29 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaaiIdacaaI0a GaaGymaaqaaiaaigdacaaIWaGaaGioaaaaaiaawIcacaGLPaaadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaey4kaSYaaSGbaeaacaaI0aaabaGaaGOm aiaaiMdaaaaaaa@498C@ if ( Y/ Y n ) ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGHKjYOdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@4050@

and

  • f( Z/ Z n )= ( Z/ Z n ) 1/3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaadMfaaeaaca WGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaamaaCaaa leqabaGaaGymaiaac+cacaaIZaaaaaaa@429E@ if ( Z/ Z n )> ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGH+aGpdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@3FA3@
  • f( Z/ Z n )=( 841/ 108 )( Z/ Z n )+4/ 29 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaaiIdacaaI0a GaaGymaaqaaiaaigdacaaIWaGaaGioaaaaaiaawIcacaGLPaaadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaey4kaSYaaSGbaeaacaaI0aaabaGaaGOm aiaaiMdaaaaaaa@498C@ if ( Z/ Z n ) ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGHKjYOdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@4050@

and X, Y, Z describe the colour stimulus considered and Xn, Yn, Zn describe a specified white achromatic stimulus

Note 1 to entry: Approximate correlates of lightness, chroma, and hue can be calculated as follows:

CIE 1976 lightness:

  • L =116f( Y/ Y n )16 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadYeadaahaaWcbe qaaiabgEHiQaaakiabg2da9iaaigdacaaIXaGaaGOnaiaadAgadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaeyOeI0IaaGymaiaaiAdaaaa@4259@

where

  • f( Y/ Y n )= ( Y/ Y n ) 1/3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaadMfaaeaaca WGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaamaaCaaa leqabaGaaGymaiaac+cacaaIZaaaaaaa@429E@ if ( Y/ Y n )> ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGH+aGpdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@3FA3@
  • f( Y/ Y n )=( 841/ 108 )( Y/ Y n )+4/ 29 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaaiIdacaaI0a GaaGymaaqaaiaaigdacaaIWaGaaGioaaaaaiaawIcacaGLPaaadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaey4kaSYaaSGbaeaacaaI0aaabaGaaGOm aiaaiMdaaaaaaa@498C@ if ( Y/ Y n ) ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGHKjYOdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@4050@

CIE 1976 a, b chroma:

  • Δ C ab * = ( a *2 + b *2 ) 1/2

CIE 1976 a, b hue angle:

  • h ab =arctan( b * / a * )

Note 2 to entry: See also CIE 15, Colorimetry.

Note 3 to entry: See also ISO/CIE 11664-4, Colorimetry – Part 4: CIE 1976 L*a*b* Colour Space.

Note 4 to entry: This entry was numbered 845-03-56 in IEC 60050-845:1987.


fr
espace chromatique L*a*b* CIE 1976, m
espace chromatique CIELAB, m
espace chromatique à trois dimensions approximativement uniforme, obtenu en portant en coordonnées rectangulaires les grandeurs L*, a*, b*, définies par les équations:
  • L*=116f( Y/ Y n )16 a*=500[ f( X/ X n )f( Y/ Y n )] b*=200[ f( Y/ Y n )f( Z/ Z n )] MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqipu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGacaGaaiaabmqaamaabaabaaGceaqabeaacaWGmb GaaiOkaiabg2da9iaaigdacaaIXaGaaGOnaiaadAgadaqadaqaamaa lyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGcca GLOaGaayzkaaGaeyOeI0IaaGymaiaaiAdaaeaacaWGHbGaaiOkaiab g2da9iaaiwdacaaIWaGaaGimamaadmaabaGaamOzamaabmaabaWaaS GbaeaacaWGybaabaGaamiwamaaBaaaleaacaqGUbaabeaaaaaakiaa wIcacaGLPaaacqGHsislcaWGMbWaaeWaaeaadaWcgaqaaiaadMfaae aacaWGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaaaGa ay5waiaaw2faaaqaaiaadkgacaGGQaGaeyypa0JaaGOmaiaaicdaca aIWaWaamWaaeaacaWGMbWaaeWaaeaadaWcgaqaaiaadMfaaeaacaWG zbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaaiabgkHiTi aadAgadaqadaqaamaalyaabaGaamOwaaqaaiaadQfadaWgaaWcbaGa aeOBaaqabaaaaaGccaGLOaGaayzkaaaacaGLBbGaayzxaaaaaaa@6779@

  • f( X/ X n )= ( X/ X n ) 1/3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaadMfaaeaaca WGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaamaaCaaa leqabaGaaGymaiaac+cacaaIZaaaaaaa@429E@ si ( X/ X n )> ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGH+aGpdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@3FA3@
  • f( X/ X n )=( 841/ 108 )( X/ X n )+4/ 29 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaaiIdacaaI0a GaaGymaaqaaiaaigdacaaIWaGaaGioaaaaaiaawIcacaGLPaaadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaey4kaSYaaSGbaeaacaaI0aaabaGaaGOm aiaaiMdaaaaaaa@498C@ si ( X/ X n ) ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGHKjYOdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@4050@

et

  • f( Y/ Y n )= ( Y/ Y n ) 1/3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaadMfaaeaaca WGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaamaaCaaa leqabaGaaGymaiaac+cacaaIZaaaaaaa@429E@ si ( Y/ Y n )> ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGH+aGpdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@3FA3@
  • f( Y/ Y n )=( 841/ 108 )( Y/ Y n )+4/ 29 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaaiIdacaaI0a GaaGymaaqaaiaaigdacaaIWaGaaGioaaaaaiaawIcacaGLPaaadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaey4kaSYaaSGbaeaacaaI0aaabaGaaGOm aiaaiMdaaaaaaa@498C@ si ( Y/ Y n ) ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGHKjYOdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@4050@

et

  • f( Z/ Z n )= ( Z/ Z n ) 1/3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaadMfaaeaaca WGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaamaaCaaa leqabaGaaGymaiaac+cacaaIZaaaaaaa@429E@ si ( Z/ Z n )> ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGH+aGpdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@3FA3@
  • f( Z/ Z n )=( 841/ 108 )( Z/ Z n )+4/ 29 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaaiIdacaaI0a GaaGymaaqaaiaaigdacaaIWaGaaGioaaaaaiaawIcacaGLPaaadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaey4kaSYaaSGbaeaacaaI0aaabaGaaGOm aiaaiMdaaaaaaa@498C@ si ( Z/ Z n ) ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGHKjYOdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@4050@

et X, Y, Z représentent les stimuli de couleurs pris en considération et Xn, Yn, Zn représentent un stimulus achromatique spécifié de couleur blanche

Note 1 à l'article: Les correspondants approximatifs de clarté, chroma et teinte peuvent être calculés comme suit:

clarté CIE 1976:

  • L =116f( Y/ Y n )16 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadYeadaahaaWcbe qaaiabgEHiQaaakiabg2da9iaaigdacaaIXaGaaGOnaiaadAgadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaeyOeI0IaaGymaiaaiAdaaaa@4259@

  • f( Y/ Y n )= ( Y/ Y n ) 1/3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaadMfaaeaaca WGzbWaaSbaaSqaaiaab6gaaeqaaaaaaOGaayjkaiaawMcaamaaCaaa leqabaGaaGymaiaac+cacaaIZaaaaaaa@429E@ si ( Y/ Y n )> ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGH+aGpdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@3FA3@
  • f( Y/ Y n )=( 841/ 108 )( Y/ Y n )+4/ 29 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaqadaqaam aalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqabaaaaaGc caGLOaGaayzkaaGaeyypa0ZaaeWaaeaadaWcgaqaaiaaiIdacaaI0a GaaGymaaqaaiaaigdacaaIWaGaaGioaaaaaiaawIcacaGLPaaadaqa daqaamaalyaabaGaamywaaqaaiaadMfadaWgaaWcbaGaaeOBaaqaba aaaaGccaGLOaGaayzkaaGaey4kaSYaaSGbaeaacaaI0aaabaGaaGOm aiaaiMdaaaaaaa@498C@ si ( Y/ Y n ) ( 6/ 29 ) 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaamaabmaabaWaaSGbae aacaWGzbaabaGaamywamaaBaaaleaacaqGUbaabeaaaaaakiaawIca caGLPaaacqGHKjYOdaqadaqaamaalyaabaGaaGOnaaqaaiaaikdaca aI5aaaaaGaayjkaiaawMcaamaaCaaaleqabaGaaG4maaaaaaa@4050@

chroma a, b CIE 1976:

  • Δ C ab * = ( a *2 + b *2 ) 1/2

angle de teinte a, b CIE 1976:

  • h ab =arctan( b * / a * )

Note 2 à l'article: Voir auss CIE 15, Colorimetry.

Note 3 à l'article: Voir aussi ISO/CIE 11664-4, Colorimetry – Part 4: CIE 1976 L*a*b* Colour Space.

Note 4 à l'article: Cet article était numéroté 845-03-56 dans l'IEC 60050-845:1987.


ar
الأبعاد الثلاثية للألوان في الفراغ طبقا للمواصفة القياسية للإنارة الدولية CIE1976

de
CIE 1976 L*a*b* Farbraum, m
CIELAB-Farbraum, m

it
spazio del colore CIE 1976 L*a*b*
spazio del colore CIELAB

ko
CIE 1976 L* a* b* 색공간

ja
CIE1976L*a*b*色空間
CIELAB 色空間

pl
przestrzeń barw CIE 1976 L*, a*, b*, f

pt
espaço cromático L* a* b* CIE 1976
espaço cromático CIELAB

zh
CIE 1976 L*a*b*色空间
CIELAB色空间

Publication date: 2020-12
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