High-luminance and high-resolution 5-in. polycrystal phosphor screen

We have developed a 5-in. poly-crystal phosphor screens for projection CRTs using poly-crystal materials as the phosphor screen substrate. The poly-crystal materials has the same excellent physicochemical characteristics as the YAG has such as high thermal conductivity and high intensity as well as high optical transparency, but also the bigger diameter of the poly-crystal faceplate can be easily obtained and the cost of the poly-crystal faceplate is only a tenth of that of the same diameter of YAG. Furthermore, poly-crystal substrate is obtained by stamping technological process. The poly-crystal phosphor screens may be satisfied to the needs of large-scale production. An experimental 48-in. rear-projection TV incorporating the projection tubes achieved more than 1600 TV lines of horizontal resolution and 1800 lumens of brightness.