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17-24-091

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

Napierian spectral internal transmittance density

An(λ); B(λ)

natural (Napierian) logarithm of the reciprocal of the spectral internal transmittance, τ(λ)
An(λ) = B(λ) = − ln τ(λ)

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

Note 2 to entry: This entry was numbered 845-04-84 in IEC 60050-845:1987.

Note 3 to entry: This entry was numbered 17-798 and 17-800 in CIE S 017:2011.

Publication date: 2020-12
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