Broadening which has its origin in the finite optical @L03515@ of one or both levels involved in the transition.
Orange Book, 2nd
ed., p. 121 [Terms
PAC, 1985, 57
, 1453. (Nomenclature, symbols, units and their usage in spectrochemical analysis - V: Radiation sources (Recommendations 1985)
) on page 1463 [Terms