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radiant efficiency, <of a source of radiation>

ηe; η

quotient of the radiant flux of the emitted radiation and the power consumed by the source

Note 1 to entry: It is necessary to specify whether the power dissipated by auxiliary equipment (such as ballasts), if any, is included in the power consumed by the source.

Note 2 to entry: The radiant efficiency has unit one.

Note 3 to entry: This entry was numbered 845-01-54 in IEC 60050-845:1987.

Note 4 to entry: This entry was numbered 17-1018 in CIE S 017:2011.

Publication date: 2020-12
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