Light emitting device with blue light LED and phosphor components
First Claim
1. A light emitting device which comprises a light emitting component having an active layer of a semiconductor and a phosphor capable of absorbing a part of light emitted from the light emitting component and emitting light of wavelength different from that of the absorbed light, wherein:
- a) said light emitting component is a LED which has an active layer comprising a gallium nitride based semiconductor containing Indium and is capable of emitting a blue color light which spectrum has a peak wavelength within the range from 420 to 490 nm, b) said phosphor is a garnet fluorescent material activated with cerium which is capable of absorbing a part of the blue color light which spectrum has a peak wavelength within the range from 420 to 490 nm and thereby emitting light having a broad emission spectrum comprising a peak wavelength existing around the range from 510 to 600 nm and a tail continuing into the region from 700 to 750 nm, and c) said emission spectrum emitted from the garnet fluorescent material activated with cerium and a spectrum of an unabsorbed light passed through said the garnet fluorescent material from said LED are capable of overlapping each other to make a continuous combined spectrum.
1 Assignment
0 Petitions
Accused Products
Abstract
The white light emitting diode comprising a light emitting component using a semiconductor as a light emitting layer and a phosphor which absorbs a part of light emitted by the light emitting component and emits light of wavelength different from that of the absorbed light, wherein the light emitting layer of the light emitting component is a nitride compound semiconductor and the phosphor contains garnet fluorescent material activated with cerium. which contains at least one element selected from the group consisting of Y, Lu, Sc, La, Gd and Sm, and at least one element selected from the group consisting of Al, Ga and In and, and is subject to less deterioration of emission characteristic even when used with high luminance for a long period of time.
79 Citations
4 Claims
-
1. A light emitting device which comprises a light emitting component having an active layer of a semiconductor and a phosphor capable of absorbing a part of light emitted from the light emitting component and emitting light of wavelength different from that of the absorbed light, wherein:
-
a) said light emitting component is a LED which has an active layer comprising a gallium nitride based semiconductor containing Indium and is capable of emitting a blue color light which spectrum has a peak wavelength within the range from 420 to 490 nm, b) said phosphor is a garnet fluorescent material activated with cerium which is capable of absorbing a part of the blue color light which spectrum has a peak wavelength within the range from 420 to 490 nm and thereby emitting light having a broad emission spectrum comprising a peak wavelength existing around the range from 510 to 600 nm and a tail continuing into the region from 700 to 750 nm, and c) said emission spectrum emitted from the garnet fluorescent material activated with cerium and a spectrum of an unabsorbed light passed through said the garnet fluorescent material from said LED are capable of overlapping each other to make a continuous combined spectrum. - View Dependent Claims (2, 3, 4)
-
Specification