The performance characteristics of yttrium oxysulfide - A new red phosphor for color television

This paper reports the performance of a new red phosphor, europium-activated yttrium oxysulfide, which has a luminous efficiency 40% greater than that of yttrium orthovanadate. The use of this phosphor in the P22 color screen of color television receivers results in gun-current ratios which are close to unity when balanced for a "white" color temperature of 9300°K. The white-field luminance is increased 20% as compared with that of vanadate P22, screens for equal power dissipation. An even greater increase in highlight brightness is obtained when the guns are driven to the limit for acceptable blooming. Because the red field requires 40% less beam current for the same luminance, there is a corresponding reduction in the stray electron level and the red-field purity is noticeably improved. A description is given of the methods used in measuring the color temperature and luminance of color television picture-tube screens.