Light emitting device and LCD backlight using the same
AssigneeSeoul Semiconductor Co., Ltd.
InventorsKyung Nam Kim, Sang Mi Park, Tomizo Matsuoka
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Abstract
The present invention provides a light emitting device which comprises blue and red light emitting diode (LED) chips and at least one phosphor for emitting green light by means of light emitted from the blue LED chip, and an LCD backlight including the light emitting device. According to the light emitting device of the present invention, uniform white light can be implemented and both high luminance and wider color reproduction range can also be obtained. Accordingly, an LCD backlight for uniform light distribution on an LCD as well as low power consumption and high durability can be manufactured using the light emitting device.
Claims9
A light emitting device, comprising:
- at least one blue light emitting diode (LED) chip;
- at least one red LED chip;
- and
- at least one phosphor for emitting green light using light emitted from the blue LED chip,
- wherein the phosphor comprises a phosphor expressed in at least one of the following chemical formulas:
- a(MIO)b(MIIO)c(MIIIA)d(MIII2O)e(MIV2O3)f(MVoOp)g(SiO2)h(MVIxOy) <Chemical Formula>
- wherein MI is at least one element selected from the group consisting of Pb and Cu, MII is at least one element selected from the group consisting of Be, Mg, Ca, Sr, Ba, Zn, Cd and Mn, MIII is at least one element selected from the group consisting of Li, Na, K, Rb, Cs, Au and Ag, MIV is at least one element selected from the group consisting of B, Al, Ga and In, MV is at least one element selected from the group consisting of Ge, V, Nb, Ta, W, Mo, Ti, Zr and Hf, MVI is at least one element selected from the group consisting of Bi, Sn, Sb, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, A is at least one element selected from the group consisting of F, Cl, Br and I, and
- wherein a, b, c, d, e, f, g, h, o, p, x and y are set in a range of 0≦a≦2, 0<b≦8, 0≦c≦4, 0≦d≦12, 0≦e≦2, 0≦f≦2, 0≦g≦10, 0≦h≦5, 1≦o≦2, 1≦p≦5, 1≦x≦2 and 1≦y≦5;
- (A1-x-yEuxMIy)(B2-yMIIy)S4 <Chemical Formula>
- wherein A is at least one element selected from the group consisting of Ba, Sr and Ca, B is at least one element selected from the group consisting of Al, Ga and In, MI is at least one rare earth element selected from the group consisting of Sc, Y, La, Gd and Lu, MII is at least one element selected from the group consisting of Mg, Zn and Be, and
- wherein x and y are set in a range of 0.005<x<0.9, 0<y<0.995 and x+y<1;
- and
- (A1-x-yEux)(MI0.5MII0.5)y)B2S4 <Chemical Formula>
- wherein A is at least one element selected from the group consisting of Ba, Sr and Ca, B is at least one element selected from the group consisting of Al, Ga and In, MI is at least one rare earth element selected from the group consisting of Sc, Y, La, Gd and Lu, MII is at least one element selected from the group consisting of Li, Na and K, and
- wherein x and y are set in a range of 0.005<x<0.9, 0<y<0.995 and x+y<1.
Dependencies are inferred from the claim text.