LIGHT-EMITTING DEVICE AND ILLUMINATING APPARATUS

• US 20080049430A1
• Filed: 07/26/2007
• Published: 02/28/2008
• Est. Priority Date: 07/26/2006
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Sakumoto, Daisuke
• Granted Patent: US 7,503,676 B2
• Time in Patent Office: Days
• US Class Current: 362/296
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/08 containing inorganic luminescent materials
• CPC Class Codes: F21K 9/68 Details of reflectors forming part of the light source
• CPC Class Codes: H01L 2933/0091 Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A light-emitting device has a base, a light-emitting chip and a light emitter. The light-emitting chip is made of semiconductor material, and is mounted on the base. The light-emitting chip generates the primary light. The light emitter includes fluorescent material being excited by the primary light to emit a secondary light. The light emitter has a first surface with uneven surface texture.

Claims

1. A light-emitting device comprising:

a base;

a light-emitting chip made of semiconductor material, mounted on the base, and generating a primary light; and

a light emitter having a first surface with uneven surface texture facing to the light-emitting chip, and including a fluorescent material being excited by the primary light to emit a secondary light.

2. A light-emitting device according to claim 1, wherein the light emitter further has a second surface such that the first surface is rougher than the second surface.

3. A light-emitting device according to claim 2, wherein the light emitter is apart from the light-emitting chip.

4. A light-emitting device according to claim 3, wherein the light emitter is made of resin containing the fluorescent material.

5. A light-emitting device according to claim 4, wherein the resin is silicone with a specific gravity included within a range from 0.9 to 1.1.

6. A light-emitting device according to claim 5, wherein the fluorescent material has a specific gravity included within a range from 3.8 to 5.1.

7. A light-emitting device according to claim 3, further comprising:

a light reflecting surface surrounding the light-emitting chip and scattering the primary light reflected by the light emitter.

8. A light-emitting device according to claim 7, wherein the light reflecting surface scatters the secondary light.

9. A light-emitting device according to claim 3, wherein the light emitter has a dome shape.

10. A light-emitting device according to claim 1, wherein the fluorescent material is distributed to be shifted to the first surface side of the light emitter.

11. A light-emitting device according to claim 1, further comprising:

a transparent material layer encapsulating the light-emitting chip, and being apart from the first surface of the light emitter.

12. A light-emitting device according to claim 1, wherein the first surface has a configuration depending on the shapes of the inner-most fluorescent materials.

13. A light-emitting device according to claim 12, wherein the light emitter has uneven structure in further inner side than the inner-most fluorescent materials.

14. A light-emitting device according to claim 13, wherein the inner-most fluorescent material emits at least a part of a wavelength range from 625 nm to 740 nm.

15. An illuminating apparatus comprising:

a substrate with a conductive pattern;

a light-emitting chip made of semiconductor material, and connected electrically to the conductive pattern; and

a light emitter including a fluorescent material, having a first surface with uneven surface texture facing to the light-emitting chip, and covering the light-emitting chip.

16. An illuminating apparatus according to claim 15, further comprising:

a light reflector disposed in the location where the light emitted from the light emitter reaches.

17. An illuminating apparatus according to claim 15, further comprising:

a lens covering the light emitter.

18. A light-emitting device comprising:

a light source generating a primary light with a first wavelength; and

a wavelength-conversion means having a first surface with uneven surface texture, and emitting a secondary light having a second wavelength different from the first wavelength depending on the primary light.

19. A light-emitting device according to claim 18, further comprising:

means for encapsulating the light source.

20. A light-emitting device according to claim 19, further comprising:

means for diffusing the primary light and emitting the primary light to the wavelength-conversion means.