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Bunsen–Roscoe law

reciprocity law

law stating that the total radiant exposure required to elicit a given photobiological or photochemical response is independent of the duration over which the exposure occurs

Note 1 to entry: The Bunsen–Roscoe law generally holds only over a given limited range of exposure durations. Reciprocity failure can occur due to repair mechanisms, recombination effects over long periods, or photon saturation for extremely short periods.

Note 2 to entry: This entry was numbered 17-114 and 17-1045 in CIE S 017:2011.

Publication date: 2020-12
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