Blue Emitting Alkaline Earth Chlorophosphate Phosphor for Cold Cathode Fluorescent Lamp, and Cold Cathode Fluorescent Lamp and Color Liquid Crystal Display Using Same

摘要

This invention provides an alkaline earth chlorophosphate phosphor for a blue light emitting cold cathode fluorescent lamp, represented by (Sr_10-k-l-m-nBa_kCa_lMg_mEu_n)(PO₄)₆Cl₂ wherein 0k≦1.5, 0≦1≦1.2, 0≦m≦0.25 and 0.05≦n≦0.3, a cold cathode fluorescent lamp using a blue light emitting phosphor represented by (Sr_10-k-l-m-nBa_kCa_lMg_mEu_n)(PO₄)₆Cl₂ wherein 0≦k≦1.5, 0≦1≦1.2, 0≦m≦0.25 and 0.05≦n≦0.3, and a color liquid crystal display device using the lamp as backlight. The phosphor causes no significant lowering in luminescence brightness over time and no significant change in luminescent chromaticity over time under excitation with ultraviolet light at a wavelength of 180 to 300 nm and, particularly when used as backlight for a liquid crystal display, can realize image display with a wide color reproduction range.