Red or the infrared luminous fluorescent substance and uses this the liquid crystal light/write valve CRT

摘要

PURPOSE: To improve the luminance and life of a phosphor by forming a red- or infrared-emitting phosphor represented by a specific formula. ;CONSTITUTION: Y₂O₃, Gd₂O₃, Cr₂O₃, Al₂O₃, and Ga₂O₃ in a specified ratio, if necessary together with one or more kinds of alkaline earth metal, are mixed, baked in air at a specified temp., ground, washed with water, and dried to give a red- or infrared-emitting phosphor, which is represented by the formula: (Y_1-x-yCr_xGd_y)₃(Al_1-zGa_z)₅O₁₂ (wherein 0.0005≤x≤0.05, 0≤y≤1, and 0≤z≤1), contains 10ppm to 0.5% alkaline earth metal, emits in a wavelength range of 600-800nm, and has an emission peak in a range of 707-730nm. A liq. crystal light bulb CRT with a high resolution is obtd. by combining a liq. crystal light bulb having a photosensitive layer comprising a hydrogenated α-silicon photoconductor with a cathode ray tube having a fluorescent panel contg. this red- or infrared-emitting phosphor.;COPYRIGHT: (C)1994,JPO&Japio