YELLOW PHOSPHOR AND WHITE LIGHT EMITTING DEVICE COMPRISING IT

摘要

Yellow phosphors which are excited by a blue light source and have a high luminescence efficiency are disclosed. Also disclosed is a method of synthesizing yellow phosphors which provides superior luminance and color purity. Also disclosed is a white light emitting device comprising the yellow phosphors which has a wide range for reproducing white colors so that a white light similar to a natural color may be obtained. One aspect of the present invention may provide a yellow phosphor represented by the following formula 1 : (Gd<SUB>1-x</SUB>Tb<SUB>x</SUB>)<SUB>3</SUB>(Ga1-<SUB>y</SUB>Q<SUB>y</SUB>)<SUB>2</SUB>Al<SUB>3</SUB>O<SUB>z</SUB>:aCe<SUP>3+</SUP>,bB<SUP>3+</SUP> (1) wherein Q is one or more elements selected from a group consisting of Si, Al, and Sc; 0=x=0.l; 0<y<0.5; z is 12 when y is 0, 12 when Q is one or more elements selected from a group consisting of Al and Sc, or 12+y when Q is Si; a is 1 to 10 mole % of (Gd, Tb); and b is 0.5 to 4 moles per 1 mole of the host medium composition.