Friday, December 26, 2008

Handbook of OSML Libraries: Emittance

CRMHT - CNRS Centre de Recherche sur les Matériaux à Haute Température, Orléans, France
Mesure indirecte de l'émittance (Includes sample data for Silicon Dioxide)

Mesure de la réflectivité et de la transmissivité normales spectrales (10 à 40 000 cm-1 soit 1 000 à 0,25 µm).

L'émissivité normale spectrale se déduit indirectement par calcul de ces deux grandeurs par application des lois de Kirchhoff ,

i.e. at each wavelength, Emissivity =1 - Reflectivity - Transmissity






Emittance-WNHandbook of OSML Libraries














E - dielectric function
N - complex refractive index
RT - reflectivity, layer transmissivity
WN - wave number
OSML Source : [Emitttance-WN]
Function Group : [Optical Functions]







Emittance-E






Emittance-E (AE) represents the fraction of the incident radiation that is absorbed (Kirchhoff law) by a sample with a plate shape. Its expression take into account for multiple reflections (no interference effects) and depends on the dielectric functions of the incident medium Ei, those of the material Eo and the thickness d of the sample.
Function signature : Emittance-E(x,Ei,Eo,Thickness)Units


The spectral dependence must be expressed in wave numbers (cm-1) and the thickness in (cm).







Emittance-N







Emittance-N (AN) represents the fraction of the incident radiation that is absorbed (Kirchhoff law) by a sample with a plate shape. Its expression take into account for multiple reflections (no interference effects) and depends on the complex refractive indexes of the incident medium Ni, those of the material No and the thickness d of the sample.
Function signature : Emittance-N(x,Ni,No,Thickness)Units


The spectral dependence must be expressed in wave numbers (cm-1) and the thickness in (cm).







Emittance-RT







Emittance-RT (ART) represents the fraction of the incident radiation that is absorbed (Kirchhoff law) by a sample with a plate shape. Its expression take into account for multiple reflections (no interference effects and depends on the reflectivity R and the layer transmissivity T of the sample.
Function signature : Emittance-RT(R,T)







Planck-WN







Planck-WN (PWN) is the wave number version of the Planck function. Its expression depends on the temperature T.
Function signature : Planck-WN(x,T)
Constants : C1=1.1910 10-6 (W.m2) C2=1.4388 (cm.K)











See Also : [Optical Functions] [Reflectance-WN] [Transmittance-WN]


Handbook of OSML Libraries

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