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spectral absorptivity, <of an absorbing material>


spectral internal absorptance of a layer of an absorbing material such that the path of the radiation is of dimension length, and under conditions in which the boundary of the material has no influence

Note 1 to entry: to entry: The unit of the quantity length has to be specified. If a new unit of length is used that is k times the magnitude of the original one, then the value of will change to .

Note 2 to entry: The spectral absorptivity has unit one.

Note 3 to entry: This entry was numbered 845-04-88 in IEC 60050-845:1987.

Note 4 to entry: This entry was numbered 17-1209 in CIE S 017:2011.

Publication date: 2020-12
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