Luminescence of ZnS:Cu,Cl Phosphor Powder Excited by Photons, an Electric Field and Cathode Rays

Abstract

ZnS:Cu,Cl phosphor powder prepared by a solid state reaction at 900oC showed a broad emission peak in 400- 600nm, consisting of blue (440nm), self-activated (470nm) and green (510nm) bands. The emission color of the phosphor powder, originating from the relative intensity of these three bands, was found to depend on the excitation method, i.e., bluish green by photons, greenish blue under an electric field, and blue by cathode rays. This behavior was thought to result from the different penetration depth of excitation energy as well as from the spatial distribution of activators in the phosphor.