15.1: Improvements Made to the Contrast Ratio of PDPs in a Bright Room by Coating the Phosphors with Pigments

In order to improve the contrast ratio of PDPs in the bright room, the reflection luminance of the panel needs to be decreased while the luminance is increased. In this particular process, we decreased the panel reflection by coating the phosphors with pigments of each color. In order to minimize the loss of brightness, we did not coat the green phosphor with its respective pigment. The main reason this was not done was due to the fact that the green phosphor is the most important emission material for the brightness of PDPs, but the green pigment is the most ineffective material in lowering the reflectance. This technique was applied to a 50″ PDP panel. The results showed a contrast ratio increase of 15% without any sacrifice of the luminance by just adjusting the transmittance of the front filter.