Diagnostics and control of three-dimensional behaviours of microdischarge in a unit cell of an ac-type plasma display panel

The influences of surface potential formed on the address electrode by the applied pulsed voltage Va combined with the accumulated charge on the behaviour of microdischarge in a unit cell of an ac-type plasma display panel was investigated in the sustain periods by systematically varying the timing and amplitude of Va. Using a special panel, which enabled three-dimensional observation from the front and side, the spatiotemporal behaviour of excited Xe atoms in the metastable (1s5) and resonance (1s4) states and the 2p state was observed by microscopic laser absorption spectroscopy and optical emission spectroscopy, respectively. When Va was applied synchronously with the rise of the sustain pulse, the discharge started from the temporal anode side and the density of Xe*(1s5) atoms distributed over the whole area between the sustain and address electrodes. When the rise of Va was set in between the fall and the rise of successive sustain pulses, a pre-discharge occurred between the address electrode and one of the sustain electrodes which had worked as a preceding anode. In both cases, the production efficiency of excited atoms was enhanced compared with the case without Va, but the increment in the former case was larger than in the latter. However, there was an optimum amplitude of Va of about 60 V.