phosphorescence
delayed emission of optical radiation which appears 10 ns or longer after the excitation
Note 1 to entry: Technically, the term "phosphorescence" should be used only for the delayed emission due to a "forbidden transition" from an excited triplet state to a ground singlet state.
Note 2 to entry: This entry was numbered 845-04-23 in IEC 60050-845:1987.
Note 3 to entry: This entry was numbered 17-880 in CIE S 017:2011.