ACIDIC NITRIDE-BASED RED FLUORESCENT MATERIAL AND WHITE LIGHT EMITTING APPARATUS USING SAME

摘要

An oxynitride-based red phosphor having an orthorhombic crystal structure represented as the chemical formula 1, is capable of emitting red or yellowish-red light caused by light in a near ultraviolet ray or blue color area, having excellent luminance by improving light-emitting efficiency more than the conventional phosphor, and rarely reducing light emitting efficiency under harsh conditions such as high temperatures, high humidity, etc. Accordingly, a white light emitting device comprising the phosphor is capable of emitting white light as a warm color, with luminance higher than the conventional phosphor, and with excellent color rendering properties, color reproducibility, and color tunable properties. A chemical formula 1 is A_2Si_4AlON_7:zEu^2+, wherein A is Sr, Br or a combination thereof, and z is greater than or equal to 0.001 and smaller than or equal to 0.3 in the formula.