The effects of sustain electrode gap variation on the luminous efficacy in coplanar-type AC plasma display panel under low- and high-xe content conditions

We investigated the effect of sustain electrode gap variation with various Xe content gas in a coplanar-type ac plasma display panel through 2-D numerical simulation to understand the inherent high-luminous-efficacy mechanism. For the low-Xe content gas condition of 5%, the optimal sustain electrode gap was found to be about 200 μm, because of the steep decrease of electric power delivered to electrons with the increase of electrode gap longer than 200 μm. On the other hand, with the high-Xe content gas of 20%, the efficacy continuously increased as the electrode gap increased beyond 200 μm. We have found that the high luminous efficacy under the condition of long electrode gap and high-Xe content gas is due to the high-electron-heating efficacy in the cathode sheath region.