Masahiko Seki

SrCaO Protective Layer for High-Efficiency PDPs

The sustain pulse voltage of the panel for 66-kPa Ne + Xe (5%-30%) is 20%-40% lower with a Sr_0.62Ca_0.38O protective layer than with a MgO protective layer. At a normal sustain voltage of 160-200 V, the luminous efficiency of the panel with the Sr_0.62Ca_0.38O protective layer for Xe (30%) is about twice as high as with the MgO protective layer for Xe (10%). The luminances of these panels are almost the same. This high efficiency at normal sustain pulse voltage and normal luminance is obtained through the combined use of the Sr_0.62Ca_0.38O protective layer and high Xe content. With regard to ion bombardment, the Sr_0.62Ca_0.38O film has a 4.5 times longer life than SrO film and nearly 80% of the life of MgO film. We also calculated the values of theoretical secondary electron emission yield gamma_imin of MgO, SrO, and CaO without energy bands in the band gap for rare gas ions and found that [ gamma_imin of MgO] les [gamma_imin of CaO] < [gamma_imin of SrO] except for the one case with He. The breakdown voltage decreases with higher gamma_imin values. As expected, the discharge voltage of the panel is much lower with the SrO protective layer than with the MgO protective layer. The discharge voltages of the panels with Sr_0.62Ca_0.38O and SrO protective layers are almost the same. These findings show that the life of the SrO protective layer can be made 4.5 times longer without any increase in the discharge voltage by adding CaO (40 at.%)

Discharge characteristics with respect to width of address electrode using three-dimensional analysis

A numerical analysis of the microdischarge in a surface-type AC plasma display cell has been made using the time-dependent, three-dimensional (3-D) fluid equations to understand the discharge characteristics. We investigate the breakdown dynamics with the width of address electrode and barrier ribs, because the typical 3-D parameters in an AC plasma display panel (AC PDP) model are the width of address electrode and the barrier ribs. It has been clarified that the width of address electrode has important role of the formation of discharge volume with the wall annihilation by barrier ribs and the accumulation of wall charges on the part of address electrode. The obtained time dependent spatial characteristics of an AC PDP discharge with the width of address electrode and the effect of wall annihilation by barrier ribs will help us to design the optimized AC PDP cells to get stable write and sustain discharges.

A 40-inch-diagonal HDTV DC plasma display

A new 40-inch-diagonal color DC plasma display is proposed on the basis of our previous 20 to 33-inch PDPs. To achieve high performance, we developed various precision fabrication technologies and a new panel driving technique to ensure sufficient memory margin for the pulse memory drive scheme. Experimental investigations result in stable reproduction of high-definition TV (HDTV) pictures with a peak white luminance of 93 cd/m/sup 2/. Several hybrid ICs for the new electrode drive technique contribute to reducing the display thickness to 8 cm. >

A 20-in. color DC gas-discharge panel for TV display

A 20-in. diagonal color gas-discharge panel with 640*448 cells and an average cell pitch of 0.65 mm has been experimentally developed using thick-film printing and photolithographic phosphor deposition techniques. Improvements in both the cell structure and fabrication technique have produced wide memory margins for the pulse memory operation. Full-size NTSC color TV pictures with excellent uniformity have been displayed with an area luminance of 17 fL and a luminous efficacy of 0.13 lm/W. >