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Area Lighting / Radiometric, photometric and colorimetric measurements: physical detectors

IEV ref 845-25-089

Symbol
ρ(θi,ϕi,θr,ϕr,xr,yr,λ)

en
bi-directional reflectance distribution function
BRDF
function describing the change with direction of irradiation (θi,ϕi) and direction of view (θr,ϕr) of the radiance of a surface element (xr,yr) in a given direction of view at a given wavelength λ, L r ( θ r , ϕ r , x r , y r ,λ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadYeadaWgaaWcbaGaaeOCaaqabaGccaGGOaGaeqiUde3aaSbaaSqa aiaabkhaaeqaaOGaaiilaiabew9aMnaaBaaaleaacaqGYbaabeaaki aacYcacaWG4bWaaSbaaSqaaiaabkhaaeqaaOGaaiilaiaadMhadaWg aaWcbaGaaeOCaaqabaGccaGGSaGaeq4UdWMaaiykaaaa@4907@ , with respect to the irradiance incident on the medium from the given direction of irradiation at the given wavelength, E i ( θ i , ϕ i ,λ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadweadaWgaaWcbaGaaeyAaaqabaGccaGGOaGaeqiUde3aaSbaaSqa aiaabMgaaeqaaOGaaiilaiabew9aMnaaBaaaleaacaqGPbaabeaaki aacYcacqaH7oaBcaGGPaaaaa@4334@

ρ( θ i , ϕ i , θ r , ϕ r , x r , y r ,λ)= d L r ( θ r , ϕ r , x r , y r ,λ) d E i ( θ i , ϕ i ,λ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai abeg8aYjaacIcacqaH4oqCdaWgaaWcbaGaaeyAaaqabaGccaGGSaGa eqy1dy2aaSbaaSqaaiaabMgaaeqaaOGaaiilaiabeI7aXnaaBaaale aacaqGYbaabeaakiaacYcacqaHvpGzdaWgaaWcbaGaaeOCaaqabaGc caGGSaGaamiEamaaBaaaleaacaqGYbaabeaakiaacYcacaWG5bWaaS baaSqaaiaabkhaaeqaaOGaaiilaiabeU7aSjaacMcacqGH9aqpdaWc aaqaaiGacsgacaWGmbWaaSbaaSqaaiaabkhaaeqaaOGaaiikaiabeI 7aXnaaBaaaleaacaqGYbaabeaakiaacYcacqaHvpGzdaWgaaWcbaGa aeOCaaqabaGccaGGSaGaamiEamaaBaaaleaacaqGYbaabeaakiaacY cacaWG5bWaaSbaaSqaaiaabkhaaeqaaOGaaiilaiabeU7aSjaacMca aeaaciGGKbGaamyramaaBaaaleaacaqGPbaabeaakiaacIcacqaH4o qCdaWgaaWcbaGaaeyAaaqabaGccaGGSaGaeqy1dy2aaSbaaSqaaiaa bMgaaeqaaOGaaiilaiabeU7aSjaacMcaaaaaaa@70E0@

Note 1 to entry: The bi-directional reflectance distribution function is expressed in steradian to the power minus one (sr−1).

Note 2 to entry: See also "radiance coefficient".

Note 3 to entry: This note applies to the French language only.


fr
fonction de répartition bidirectionnelle du facteur de réflexion, f
BRDF, f
fonction décrivant la variation, avec la direction d'irradiation (θi,ϕi) et la direction de vision (θr,ϕr) de la luminance énergétique d'un élément de surface (xr,yr) dans une direction d'observation donnée et à une longueur d'onde donnée λ, L r ( θ r , ϕ r , x r , y r ,λ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadYeadaWgaaWcbaGaaeOCaaqabaGccaGGOaGaeqiUde3aaSbaaSqa aiaabkhaaeqaaOGaaiilaiabew9aMnaaBaaaleaacaqGYbaabeaaki aacYcacaWG4bWaaSbaaSqaaiaabkhaaeqaaOGaaiilaiaadMhadaWg aaWcbaGaaeOCaaqabaGccaGGSaGaeq4UdWMaaiykaaaa@4907@ , par rapport à l'éclairement énergétique incident sur le milieu à partir de la direction d'irradiation donnée à la longueur d'onde donnée, E i ( θ i , ϕ i ,λ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadweadaWgaaWcbaGaaeyAaaqabaGccaGGOaGaeqiUde3aaSbaaSqa aiaabMgaaeqaaOGaaiilaiabew9aMnaaBaaaleaacaqGPbaabeaaki aacYcacqaH7oaBcaGGPaaaaa@4334@

ρ( θ i , ϕ i , θ r , ϕ r , x r , y r ,λ)= d L r ( θ r , ϕ r , x r , y r ,λ) d E i ( θ i , ϕ i ,λ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai abeg8aYjaacIcacqaH4oqCdaWgaaWcbaGaaeyAaaqabaGccaGGSaGa eqy1dy2aaSbaaSqaaiaabMgaaeqaaOGaaiilaiabeI7aXnaaBaaale aacaqGYbaabeaakiaacYcacqaHvpGzdaWgaaWcbaGaaeOCaaqabaGc caGGSaGaamiEamaaBaaaleaacaqGYbaabeaakiaacYcacaWG5bWaaS baaSqaaiaabkhaaeqaaOGaaiilaiabeU7aSjaacMcacqGH9aqpdaWc aaqaaiGacsgacaWGmbWaaSbaaSqaaiaabkhaaeqaaOGaaiikaiabeI 7aXnaaBaaaleaacaqGYbaabeaakiaacYcacqaHvpGzdaWgaaWcbaGa aeOCaaqabaGccaGGSaGaamiEamaaBaaaleaacaqGYbaabeaakiaacY cacaWG5bWaaSbaaSqaaiaabkhaaeqaaOGaaiilaiabeU7aSjaacMca aeaaciGGKbGaamyramaaBaaaleaacaqGPbaabeaakiaacIcacqaH4o qCdaWgaaWcbaGaaeyAaaqabaGccaGGSaGaeqy1dy2aaSbaaSqaaiaa bMgaaeqaaOGaaiilaiabeU7aSjaacMcaaaaaaa@70E0@

Note 1 à l'article: La fonction de répartition bidirectionnelle du facteur de réflexion est exprimée en stéradian à la puissance moins un (sr−1).

Note 2 à l'article: Voir aussi "coefficient de luminance énergétique".

Note 3 à l'article: Le terme abrégé "BRDF" est dérivé du terme anglais développé correspondant "bi-directional reflectance distribution function".


ar
دالة توزيع إنعكاسية ثنائية الاتجاه

de
Bidirektionale Reflexionsgradverteilungsfunktion, f
BRDF, f

it
funzione di distribuzione della riflettanza bidirezionale
BRDF

ko
양 방향 반사율 분산 함수

ja
二方向反射率分布関数
双方向反射率分布関数

pl
funkcja rozkładu odbicia dwukierunkowego, f

pt
função de distribuição bidirecional do fator de reflexão
BRDF

zh
双向反射率分布函数

Publication date: 2020-12
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