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spectral absorbance, <of a homogeneous non-diffusing layer>

spectral internal transmittance density


logarithm to base 10 of the reciprocal of the spectral internal transmittance, τ(λ)
Ai(λ) = −log10 τ(λ)

Note 1 to entry: The spectral absorbance has unit one.

Note 2 to entry: This entry was numbered 845-04-83 in IEC 60050-845:1987.

Note 3 to entry: This entry was numbered 17-1207 and 17-1216 in CIE S 017:2011.

Publication date: 2020-12
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