A volume-averaged, zero-dimensional numerical simulator for ac discharge of plasma display panel (PDP) is developed. The vacuum-ultraviolet photons such as 147 and 173 nm are treated as particles that cannot be stored. The surface charge on the dielectric layer is introduced in this study. Solving particle continuity and electron energy balance equations simultaneously, the characteristics of ac-discharge phenomena, such as the temporal evolution of surface charge, electric field, and particle densities, are analyzed. This numerical simulation result shows that the increment of the percentage of xenon atoms in a neon-xenon mixture of PDP improves the luminous efficiency of the ac-discharge gas by raising the intensity of 173 nm vacuum-ultraviolet photons from xenon excimers. (C) 2007 American Vacuum Society.