| US 7,564,065 B2 | ||
| Light emitting device and a lighting apparatus | ||
| Ken Sakuma, Sakura (Japan); and Naoto Hirosaki, Tsukuba (Japan) | ||
| Assigned to Fujikura Ltd., Tokyo (Japan); and National Institute for Materials Science, Ibaraki (Japan) | ||
| Filed on Mar. 22, 2005, as Appl. No. 11/85,070. | ||
| Claims priority of application No. P2004-83399 (JP), filed on Mar. 22, 2004. | ||
| Prior Publication US 2007/0278510 A1, Dec. 06, 2007 | ||
| Int. Cl. H01L 33/00 (2006.01); H01L 31/12 (2006.01); H01J 1/62 (2006.01); H01J 63/64 (2006.01) | ||
| U.S. Cl. 257—80 [257/79; 257/81; 257/82; 257/83; 257/84; 257/88; 257/98; 257/99; 257/100; 257/101; 257/102; 257/103; 313/496; 313/497; 313/498; 313/499; 313/500; 313/501] | 4 Claims |
| 1. A light emitting device comprising:
a semiconductor light emitting element that emits purplish blue or blue light, and
a phosphor that absorbs part or all of the light emitted from said semiconductor light emitting element and emits fluorescence
having a different wavelength from the wavelength of said light,
wherein said phosphor is a mixture of X percent of a first phosphor material that emits yellow green, yellow or yellow orange
light and Y percent of a second phosphor material that emits light having a color of yellow orange or orange and a longer
dominant wavelength than said first phosphor material, said first and said second phosphor material being mixed in a manner
that satisfy all the following relations 0<X≤100, 0≤Y<100, and 0<(X+Y)≤100, and
wherein said first phosphor material is a SiAlON phosphor represented by a general formula Cax(Si, Al)12(O,N)16:Euy2+ and a main phase thereof has an alpha SiAlON crystal structure, wherein said SiAlON phosphor has a composition x of from
0.75 to 1.0 and a composition y of from 0.04 to 0.25; and
wherein said second phosphor material is a nitride red phosphor represented by a general formula Ca1-xAlSiN3:Eux2+, wherein both Ca and Eu are present in said second phosphor material.
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