Sang-hun Jang

Production efficiency of excited atoms in PDP cells with grooved dielectric structures studied by laser absorption spectroscopy

Performances of microplasmas in unit discharge cells with grooved structures in the dielectric layer covering the coplanar electrodes were investigated in alternating current (ac)-type plasma display panels filled with Ne-Xe(10%) mixture at 450 torr. The diagnostics are based on a microscopic laser-absorption spectroscopy technique for the spatiotemporally resolved measurements of absolute densities of Xe/sup */(1s/sub 5/,1s/sub 4/) atoms, from which the production rate and the efficiency of the vacuum ultraviolet photons were estimated. These results were compared with previously reported data obtained in conventional phosphor coated panels with the same structures for the dependences on the applied sustain voltages. As the result, the following conclusions were ascertained. The grooved structure does not help to improve the luminous efficiency but it helps to lower the firing and sustaining voltages by about 20 V if the electrode gap is kept constant. Therefore, it provides additional possibilities for the selection of other operating conditions such as the gas composition and pressure for the improvements of the luminance and the luminous efficiency.

8.2: New Electrode Structure to Improve Discharge Characteristics in AC PDPs

A new structure including igniter electrode is proposed to achieve a low sustaining voltage and high luminous efficacy. By measuring minimum sustaining voltage(Vsm), discharge current(Ion), displacement current(Ioff) and brightness of the light from a 6-inch AC PDP, performances of the conventional structure and the igniter structure are compared. When compared with the conventional structure, the igniter structure showed 10% Vsm improvement at the Ne-Xe(10%) gas mixture of 600 mbar. Therefore, we could apply the higher partial pressure of Ne-Xe(12%) to the igniter structure, which results in 42% luminous efficacy improvement at the similar sustaining voltage range.

14.4: Plasma Display Panel with Ridged Dielectric Layer between Sustaining Electrodes

This article presents a front panel structure for an alternating current plasma display panel (AC PDP) based on a ridged transparent dielectric layer between the sustaining electrodes. Compared to a conventional AC PDP, the suggested structure can reduce a firing voltage and sustaining voltage due to a strong electric field between the sustaining electrodes. First experiments were conducted to see the effect of ridged dielectric structure in the short electrode gap of 110 μm with various Xe contents from 10% to 50% at a gas pressure of 450 Torr, and the results confirmed that the ridged dielectric structure reduced the firing and sustaining voltages by about 74 and 79 V at 10% Xe content compared to a conventional structure with 10% Xe content, respectively. Also, the proposed structure improved the luminous efficacy and luminance by about 50.9% and 33%, respectively, with 50% Xe content when compared to a conventional structure with 10% Xe content at a similar driving voltage. Second, performances of the conventional structure and the ridged dielectric structure with the electrode gap of 140 μm were compared. Experimental results confirmed that the box shaped ridged dielectric structure could be driven at a lower voltage than conventional AC-PDPs with the same Xe content. Also, the luminous efficacy of box shaped ridged dielectric structure was higher than those of conventional structures.

P-71: Cross-Shaped Cell Structure Employing Auxiliary Address Pulse Driving Scheme in AC-PDP

This paper proposes a cross-shaped cell structure employing an auxiliary address pulse driving scheme for the high luminous efficiency of AC-PDP. The discharge characteristics of the conventional stripe-type and cross-shaped cell structures are compared under a sustain driving frequency of 50 kHz in the 6-inch test panel with a pressure of 450 Torr and a 10 % Xe-content gas mixture. The cross-shaped cell structure shows a higher luminous efficiency than the conventional stripe-type cell structure in conventional driving scheme. As result of adopting an auxiliary address pulse driving scheme, the luminous efficiency of the cross-shaped cell structure increases by about 44 % (2.38 lm/W) than that of the conventional case (1.64 lm/W) under 10 % Xe partial pressure.