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radiant flux

radiant power

Φe; Pe; Φ; P

change in radiant energy with time

where Qe is the radiant energy emitted, transferred or received, and t is time

Note 1 to entry: The corresponding photometric quantity is "luminous flux". The corresponding quantity for photons is "photon flux".

Note 2 to entry: The term "radiant flux" is the preferred term for most radiometric applications, with the notable exception of laser radiometry where the term "radiant power" is more commonly used.

Note 3 to entry: The radiant flux is expressed in watt (W).

Note 4 to entry: This entry was numbered 845-01-24 in IEC 60050-845:1987.

Note 5 to entry: This entry was numbered 17-1025 and 17-1027 in CIE S 017:2011.

Publication date: 2020-12
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