Patent ID: 8550645

Claim:
An illumination device for a display device, which comprises a substrate and a plurality of white light-emitting devices disposed on top of the substrate, and can be used as a backlight for a liquid crystal display panel, wherein the white light-emitting devices have a light source and a phosphor that is excited by the light source and emits light, and a fluorescent material with a composition represented by a general formula: M(0) a M(1) b M(2) x−(vm+n) M(3) (vm+n)−y O n N z−n is used as the phosphor, wherein M(0) represents one or more elements selected from the group consisting of Li, Na, Be, Mg, Ca, Sr, Ba, Sc, Y, La, Gd and Lu, M(1) represents one or more activators selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm and Yb, M(2) represents one or more elements selected from the group consisting of Si, Ge, Sn, Ti, Hf and Zr, M(3) represents one or more elements selected from the group consisting of Be, B, Al, Ga, In, Tl and Zn, O represents elemental oxygen, N represents elemental nitrogen, x, y and z are numbers that satisfy 33≦x≦51, 8≦y≦12 and 36≦z≦56 respectively, a and b are numbers that satisfy 3≦a+b≦7 and 0.001≦b≦1.2, m and n are numbers which, when me=a+b, satisfy 0.8·me≦m≦1.2·me and 0≦n≦7, and v is a number which, when v(0) represents a valency of an M(0) ion and v(1) represents a valency of an M(1) ion, satisfies v={a·v(0)+b·v(1)}/(a+b).