Advanced discharge modes in an ac plasma display with an auxiliary electrode

Abstract

The characteristics of advanced discharge modes were investigated through measurements of spatiotemporal infrared emission, discharge current, infrared intensity, and luminous efficacy in an ac plasma display panel with an auxiliary electrode located between scan and common electrodes. Pulse waveforms that included auxiliary pulses applied to the auxiliary electrode after every sustain pulse were used. The proposed advanced discharge modes are as follows: In mode 1, strong discharges are generated by the sustain pulses only, whereas strong discharges are generated by the sustain pulses and a weak discharge is generated by the auxiliary pulse applied after the scan pulse in mode 2. In mode 3-1, strong discharges are generated by the sustain pulses and weak discharges are generated by the auxiliary pulses applied after the scan and common pulses, while all sustain and auxiliary pulses generate discharges having similar intensities in mode 3-2. Mode 1 and mode 2 are efficient modes; the luminous efficacy was improved in mode 1 owing to more homogeneous discharge due to the auxiliary electrode and a priming effect due to the auxiliary pulse. The luminous efficacy was also improved in mode 2, because of decreased power consumption induced by a decrease in wall charges and sustained or increased luminance due to priming particles. Mode 3-1 and mode 3-2 are inefficient modes; the luminous efficacy was reduced in mode 3-1 as a result of a decrease in the luminance due to insufficiently generated priming particles. The luminous efficacy was also reduced in mode 3-2, because of short-coplanar-gap discharges of the sustain pulses. It was found that advanced discharge modes were changed successively from mode 1 to mode 3-2 when sustain or auxiliary pulses of higher voltage were applied. The maximum luminous efficacy can be obtained in mode 1 at a low sustain pulse voltage and in mode 2 at mid and high sustain pulse voltages.