The phosphor degradation characteristics of ac-driven plasma display panels (PDPs) upon vacuum UV (VUV) irradiation and ion bombardment were investigated. For experimental investigation, the specific apparatus was set up so that the intensity of the VUV and ion energy was measured and compared with those of the PDP cell while operating in ac mode. Then, the lifetime of the PDP phosphor was analyzed in terms of degradation. Experimental observations coincide well with known phosphor degradation characteristics such as a faster decrease of photoluminescence of BaMgAl10O17:Eu2+ on VUV irradiation and ZnSiO4:Mn2+ on ion bombardment. The results also show that the deterioration of phosphor lifetime by ion damage that occurs on the surface is a factor that has a considerable impact on the conditions of PDP operation. Furthermore, this simple experimental approach to investigating phosphor degradation is well suited to identify phosphors and coatings for PDP application. (C) 2008 The Electrochemical Society.