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spectral external radiant efficiency of the fluorescent specimen


quotient of the total radiant flux of all wavelengths emitted by the fluorescent process for an excitation wavelength and the total radiant excitation power irradiating the fluorescent material

Note 1 to entry: This quantity is also measured in relative terms by comparison to the radiant flux reflected from the perfect reflecting diffuser identically irradiated and viewed for a given excitation wavelength.

Note 2 to entry:
Fluorescence is understood to include both fluorescent and phosphorescent phenomena with time constants short enough to be ignored for the application.

Note 3 to entry: The spectral external radiant efficiency of the fluorescent specimen has unit one.

Publication date: 2020-12
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