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optical light output ratio, <of a luminaire>

quotient of the total luminous flux of the luminaire, measured under specified conditions, and the sum of the individual luminous fluxes of the lamps when they are inside the luminaire

Note 1 to entry: For luminaires using incandescent lamps only, the optical light output ratio and the light output ratio are the same in practice.

Note 2 to entry: The optical light output ratio has unit one.

Note 3 to entry: This entry was numbered 845-09-38 in IEC 60050-845:1987.

Note 4 to entry: This entry was numbered 17-847 in CIE S 017:2011.

Publication date: 2020-12
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