quantum efficiency

Definition: Measure of effectiveness of light-sensitive system: (1) In a photo-detector: the ratio of induced current to incident flux: measured in electrons per photon or amps/watt. * May be measured in terms of photons absorbed. (2) In sensitised film: the number of silver halide crystals made developable per unit light flux incident or absorbed. (3) In a source of radiation: the ratio of the number of photons emitted to the number of electrons flowing through.

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