Infrared‐induced changes in the emission spectra of ZnS powder phosphors

摘要

The effect of infrared (0.8 and 1.25 mgr;) on the luminescent spectra of copper, silver, and self‐activated ZnS powder phosphors was investigated at room and liquid‐nitrogen temperatures under ultraviolet excitation. The equilibrium change in luminescence (quenching or enhancement) was found to depend on the portion of the emission spectrum observed, as well as on the temperature and the infrared wavelength used. These effects can be explained by noting that the freed holes may be retrapped at nonionized activator levels or recombine nonradiatively with trapped electrons.