radiant efficiency

[2.6.2]  (of a source of radiation) (η_e)

Ratio of the radiant flux of the emitted radiation to the power consumed by the source. Unit: 1.^*

Note: It must be specified whether or not the power dissipated by any auxiliary equipment such as ballasts, if any, is included in the power consumed by the source.

^{*. CIE S 017/E:2020, ILV: International Lighting Vocabulary, 2nd edition, Vienna: International Commission on Illumination (CIE); 2020.}