| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a white LED which is preferable in light-emitting efficiency and power, usable for a long term with preferable stability, and capable of changing white light to medium color light, and additionally, applicable to a wide range of use. <P>SOLUTION: Blue LED crystal grains whose wavelengths are 425-475 nm are coated with green, red color mixed fluorescent powder. The component of green fluorescent powder is selected from among Li<SB>2</SB>TiO<SB>3</SB>:Mn, LiAlO<SB>2</SB>:Mn, 6MgO-As<SB>2</SB>O<SB>5</SB>-Mn<SP>4+</SP>or 3.5MgO-0.5MgF<SB>2</SB>-GeO<SB>2</SB>-Mn<SP>4+</SP>. The component of red fluorescent powder is selected from among Y<SB>3</SB>(Ga<SB>X</SB>Al<SB>1-X</SB>)<SB>5</SB>O<SB>12</SB>:Ce(0<x<1), La<SB>2</SB>O<SB>3</SB>-11Al<SB>2</SB>O<SB>3</SB>:Mn or Ca<SB>8</SB>Mg(SiO<SB>4</SB>)<SB>4</SB>Cl<SB>2</SB>:Eu, Mn. The white light is emitted by mixing the blue light with the light emitted from the mixed fluorescent powder when it is excited by the blue light from the blue LED crystal grains. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
