Studies on new YAG phosphor screen for HDTV projector

摘要

The paper makes a systematic exposition of the theory and technology of a new kind of yttrium aluminum oxide garnet (YAG) phosphor screen (2 approximately 3 inches diagonal) - the heart of a large screen (greater than 72 inches diagonal) HDTV projector with high brightness, high resolution and good contrast ratio. According to YAG's characteristics of high heat conductivity and high hardness and strength, we propose creatively the idea: fabricating YAG phosphor screen by depositing phosphor powder on YAG film. The YAG phosphor screen' capability of conducting heat is ten times greater than the conventional CRT phosphor screen, with the help of liquid cooling, the YAG phosphor screen avoids to some extent the phosphor's saturation and degradation by high density electron bombardment existing seriously in conventional CRT projector phosphor screen, so the YAG phosphor screen obtains very high brightness and good contrast ratio. Owing to the very small thickness, big refractive index of YAG film and the high density phosphor layer prepared by improved sedimentation and centrifugal sedimentation technics, the resolution of the YAG phosphor screen is high.