P‐58: Optimization of the Luminous Efficiency of Plasma Display Panels Using Numerical Modeling

Abstract

A two-dimensional model is used to study the effect of cell structure on the performance of PDPs. More specifically, the effect of the insertion of a floating conducting material between the dielectric layer and the MgO film on the performance of the device is investigated. The shape of the discharge power pulse is found to be significantly different in comparison with the corresponding pulse of the standard cell geometry. It is also found that this cell structure results in a more confined discharge. IntroductionPlasma display panels (PDPs) are one of the leading candidates in the competition for large-size, high-brightness flat panel displays, suitable for high-definition television monitors.PDP cells are small and provide limited access for diagnostic measurements. PDP parameters which can be measured experimentally are still insufficient to provide a quantitative understanding of the discharge dynamics. As a result, computer modeling is currently essential for understanding PDP physics and optimizing its operation [1,2]. The goal of this work is to use twodimensional simulations to provide better understanding of the underlying physics that determine the efficiency of the cell structure. More specifically, we investigate the effect of the insertion of a floating conducting material between the dielectric layer and the MgO film on the performance of the device. Such an arrangement has recently been proposed as a way to substantially increase the luminous efficiency [3]. Model DescriptionThe model utilized here is based on a self-consistent simulation of the microdischarges in the PDP cell. ) and UV emission at 147 nm, 150 nm, and 173 nm. The electron-impact ionization and excitation frequencies as well as the electron drift velocity are calculated as a function of the reduced electric field E/N using the Boltzmann code ELENDIF [4]. A semi-implicit numerical technique is used for the solution of the system of equations [5]. The capacity matrix method [6] is used for the numerical treatment of the floating conducting electrodes inserted in the dielectric layer. Results Cell Geometry and Driving WaveformThe geometry of the PDP cell used in the simulations is shown in Figure 1a. The relative permittivity of the dielectrics is 10. The gas mixture filling the region between the dielectrics is a 4% XeNe mixture at a pressure of 500 Torr. The secondary electron emission coefficients for Ne and Xe ions on MgO are taken to be 0.5 and 0.01 respectively. The width of the cell L is 1260 µm, the gas gap length D is 150 µm, and the thickness of the dielectric layers d is 30 µm. The width w of the X and Y electrodes is set to 300 µm. In order to compare our results with the results reported in [3], we only apply sustain pulses between the X and Y electrodes, as is shown in Figure 1b. We do not include the address electrode in the simulation results reported here. The driving voltage waveform consists of a sequence of 4 µs pulses (Figure 1b). The rise and fall times of all pulses are 100 ns. A pulse of amplitude V i i...

Improve the luminous efficiency of AC plasma display by high-frequency driving on address electrodes

“…Much work has been done to improve the luminance and luminous efficiency recently, but more enhancements are necessary for PDP to become a competitive product on the market. From the structure and lighting mechanism points of view, these needed enhancements can be achieved through the better design of cell and electrode geometries [1], [2], compositions of the gas mixture [3], materials of phosphors, driving circuit [4], and driving waveform [5]- [9]. Each fashion has its own applicability and different level of improvement, and some of them can possibly be combined to gain higher luminous efficiency.…”