We developed material and process technologies concerned to DDF, which is formed on MgO surface around the inter-pixel gap to prevent vertical crosstalk discharge in stripe rib structure. First we tried with thin film deposition and lift-off patterning to find Al2O3 and TiO2 are both available for DDF material. Next we tried with thick film printing in favor of mass productivity for large size PDPs. In case DDF included PbO glass, we met serious hardship in generating discharge. The problem was perfectly solved by having thick film DDF composed of 100 nm sized Al2O3 grains without glass component. Its γi was about 1/5 that of MgO, suggesting that the thick film DDF is almost compatible with thin film Al2O3 in electron emission characteristics. Such very small grain size contributes to DDF transparency, which is excellently high. In addition to it, such DDF is equipped with cushioning effect to prevent dot defects caused by rib breakage. Furthermore the DDF functions as getter during panel exhaustion to bring deep blue color by promoting deoxidization of blue phosphor provided that its volume is small enough. Transparent DDF may be rather better than black one with respect to bright room contrast ratio, not to mention to avoiding terrible sparking discharge. Thus material and process technologies for DDF have been almost fixed in success.

We propose a new cell configuration which newly employs discharge deactivation film (DDF). DDF is formed on MgO surface in stripe figure to cover it around the boundary of neighboring display lines. DDF prevents discharge cross talk between the lines even in case of stripe rib structure by virtue of its low secondary electron emission coefficient (γi). DDF also makes better address discharge response because it presumably moves address discharge closer to the surface dischage gap. On behalf of mass productivity for large size PDPs DDF is formed by simple screen-printing and firing method. And it consists of very fine Al2O3 grains without any inorganic binder. Such DDF is visually transparent and then helpful for high luminance and luminous efficiency. In addition to it, such DDF is presumably equipped with gas purifying character and then helpful for deep blue color and good white color balance accordingly. Further, DDF combined with sustain electrodes in specific figure which we call "CAPABLE DDF" brings about so high luminous efficiency for stripe rib structure as it may surpass box rib one. This probably means that vertically open discharge space in stripe rib structure is advantageous for high luminous efficiency. In our latest work for 46 inch-high definition PDPs, 2.1 lm/W and 1200 cd/m2 were both achieved under practical driving condition. Still it will be as high as 2.4 lm/W if each sustain electrode is shared by neighboring display lines. CAPABLE DDF allows more tolerance in DDF printing process. It also makes optical cross talk negligible even in stripe rib structure. And its durability against long time operation proved to have no specific problem. This presumably means that re-landing of sputtered MgO never reaches DDF surface. We believe this new technology can promise the future of stripe rib.