# e-ILV

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# 17-21-037

luminous energy

DEPRECATED: quantity of light

Qv; Q

energy of electromagnetic waves weighted by the spectral luminous efficiency multiplied by maximum luminous efficacy of a specified photometric condition

Note 1 to entry: Luminous energy for photopic vision is expressed by

where Qe,λ(λ) is the spectral radiant energy at wavelength λ, V(λ) is spectral luminous efficiency, and Km is maximum luminous efficacy.

Note 2 to entry: The term "quantity of light" is no longer used.

Note 3 to entry: Luminous energy can be emitted, transferred or received.

Note 4 to entry: Luminous energy can be expressed by the time integral of the luminous flux, Φv, over a given duration, Δt
.

Note 5 to entry: The corresponding radiometric quantity is "radiant energy". The corresponding quantity for photons is "photon energy".

Note 6 to entry: The luminous energy is expressed in lumen second (lm·s) or lumen hour (lm·h).

Note 7 to entry: This entry was numbered 845-01-28 in IEC 60050-845:1987.

Note 8 to entry: This entry was numbered 17-733 and 17-1007 in CIE S 017:2011.

Publication date: 2020-12