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Area Lighting / Emission, optical properties of materials

IEV ref845-04-80

Symbol
δ(λ)

en
spectral optical thickness
spectral optical depth (of a medium, for a given length)
quantity used in atmospheric physics and physical oceanography : for a monochromatic component of wavelength λ of the radiation of a collimated beam propagating along the given length from the point x1 to the point x2 on its path through a homogeneous or non-homogeneous diffusing medium, the spectral optical thickness δ(λ) of the medium between x1 and x2 is defined by the formula

δ( λ )= x 1 x 2 μ( x,λ ) dx MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiabes7aKnaabmaabaGaeq4UdWgacaGLOaGaayzkaaGaeyypa0Zaa8qmaeaacqaH8oqBdaqadaqaaiaadIhacaqGSaGaeq4UdWgacaGLOaGaayzkaaaaleaacaWG4bWaaSbaaKGaafaacaaIXaaabeaaaSqaaiaadIhadaWgaaqccauaaiaaikdaaeqaaaqdcqGHRiI8aOGaaGjcVlaabsgacaWG4baaaa@4BD3@

where μ(x,λ) is the spectral linear attenuation coefficient at the location of dx

unit : 1

Note 1 – The spectral radiant flux Φe, λ (x1, λ) of the beam at the point x1 is reduced to the value of Φe, λ (x2, λ) at the point x2 according to the formula

Φ e,λ ( x 2 ,λ )= Φ e,λ ( x 1 ,λ ) e δ( λ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiabfA6agnaaBaaale aacaqGLbGaaeilaiabeU7aSbqabaGcdaqadaqaaiaadIhadaWgaaWc baGaaGOmaaqabaGccaqGSaGaeq4UdWgacaGLOaGaayzkaaGaeyypa0 JaeuOPdy0aaSbaaSqaaiaabwgacaqGSaGaeq4UdWgabeaakmaabmaa baGaamiEamaaBaaaleaacaaIXaaabeaakiaabYcacqaH7oaBaiaawI cacaGLPaaacqGHflY1caqGLbWaaWbaaSqabeaacqGHsislcqaH0oaz daqadaqaaiabeU7aSbGaayjkaiaawMcaaaaaaaa@5531@

so that

δ( λ )=ln Φ e,λ ( x 2 ,λ ) Φ e,λ ( x 1 ,λ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiabes7aKnaabmaaba Gaeq4UdWgacaGLOaGaayzkaaGaeyypa0JaeyOeI0IaaGPaVlaabYga caqGUbGaaGPaVpaalaaabaGaeuOPdy0aaSbaaSqaaiaabwgacaGGSa Gaeq4UdWgabeaakmaabmaabaGaamiEamaaBaaaleaacaaIYaaabeaa kiaacYcacqaH7oaBaiaawIcacaGLPaaaaeaacqqHMoGrdaWgaaWcba GaaeyzaiaacYcacqaH7oaBaeqaaOWaaeWaaeaacaWG4bWaaSbaaSqa aiaaigdaaeqaaOGaaiilaiabeU7aSbGaayjkaiaawMcaaaaaaaa@56DC@

Note 2 – For a homogeneous non-diffusing layer, δ(λ) is the Napierian spectral internal transmittance density.


[SOURCE: 845-04-84]


fr
épaisseur optique spectrale, f
profondeur optique spectrale (d'un milieu, pour une longueur donnée) f
grandeur utilisée en physique de l'atmosphère et en océanographie physique: pour une composante monochromatique de longueur d'onde λ, du rayonnement d'un faisceau quasi parallèle se propageant sur la longueur donnée du point x1 au point x2 de son trajet dans un milieu homogène ou non et diffusant, l'épaisseur optique spectrale δ(λ) du milieu entre x1 et x2 est définie par la formule

δ( λ )= x 1 x 2 μ( x,λ ) dx MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiabes7aKnaabmaabaGaeq4UdWgacaGLOaGaayzkaaGaeyypa0Zaa8qmaeaacqaH8oqBdaqadaqaaiaadIhacaqGSaGaeq4UdWgacaGLOaGaayzkaaaaleaacaWG4bWaaSbaaKGaafaacaaIXaaabeaaaSqaaiaadIhadaWgaaqccauaaiaaikdaaeqaaaqdcqGHRiI8aOGaaGjcVlaabsgacaWG4baaaa@4BD3@

оù μ(x,λ) est le coefficient d'atténuation linéique spectral à l'emplacement de dx

unité : 1

Note 1 – Le flux énergétique spectral Φe,λ (x1, λ) du faisceau au point x1 est réduit à la valeur Φe,λ (x2, λ) au point x2 selon la formule

Φ e,λ ( x 2 ,λ )= Φ e,λ ( x 1 ,λ ) e δ( λ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiabfA6agnaaBaaale aacaqGLbGaaeilaiabeU7aSbqabaGcdaqadaqaaiaadIhadaWgaaWc baGaaGOmaaqabaGccaqGSaGaeq4UdWgacaGLOaGaayzkaaGaeyypa0 JaeuOPdy0aaSbaaSqaaiaabwgacaqGSaGaeq4UdWgabeaakmaabmaa baGaamiEamaaBaaaleaacaaIXaaabeaakiaabYcacqaH7oaBaiaawI cacaGLPaaacqGHflY1caqGLbWaaWbaaSqabeaacqGHsislcqaH0oaz daqadaqaaiabeU7aSbGaayjkaiaawMcaaaaaaaa@5531@

de sorte que

δ( λ )=ln Φ e,λ ( x 2 ,λ ) Φ e,λ ( x 1 ,λ ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiabes7aKnaabmaaba Gaeq4UdWgacaGLOaGaayzkaaGaeyypa0JaeyOeI0IaaGPaVlaabYga caqGUbGaaGPaVpaalaaabaGaeuOPdy0aaSbaaSqaaiaabwgacaGGSa Gaeq4UdWgabeaakmaabmaabaGaamiEamaaBaaaleaacaaIYaaabeaa kiaacYcacqaH7oaBaiaawIcacaGLPaaaaeaacqqHMoGrdaWgaaWcba GaaeyzaiaacYcacqaH7oaBaeqaaOWaaeWaaeaacaWG4bWaaSbaaSqa aiaaigdaaeqaaOGaaiilaiabeU7aSbGaayjkaiaawMcaaaaaaaa@56DC@

Note 2 – Pour une couche homogène non diffusante, δ(λ) est la densité optique interne spectrale népérienne par transmission.


[SOURCE: 845-04-84]


ar
سماكة طيفية بصرية

de
spektrale optische Dicke, f
spektrale optische Tiefe (eines Mediums, für eine gegebene Weglänge), f

es
espesor óptico espectral

fi
spektrinen optinen syvyys
spektrinen optinen paksuus

it
spessore ottico spettrale

ko
분광 광학적 두께
분광 광학 두께

ja
分光光学的厚さ

no
nb spektral optisk tykkelse

nn spektral optisk tykkelse

pl
grubość optyczna widmowa
głębokość optyczna widmowa (ośrodka dla danej długości)

pt
espessura óptica espectral
profundidade óptica espectral (de um meio, para um comprimento dado)

sv
optiskt djup

Publication date: 1987
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