White light source and illumination apparatus using the same

• US 7,518,150 B2
• Filed: 03/03/2006
• Issued: 04/14/2009
• Est. Priority Date: 03/07/2005
• Status: Active Grant

• Current Assignee: Citizen Electronics Company Limited
• Original Assignee: Citizen Electronics Company Limited
• Inventors: Aihara, Kenshi
• Primary Examiner(s): Louie; Wai-Sing
• Assistant Examiner(s): ARMAND, MARC ANTHONY
• Application Number:
  US11/367,019
• Publication Number:
  US 20060197098A1
• Time in Patent Office: 1,138 Days
• Field of Search: 257/13, 257 79-103, 257/E51.018, 257/E33.001, 257/E33.054
• US Class Current: 257/79
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials

Abstract

A light emitting device including a blue-system semiconductor light emitting element, a green-system semiconductor light emitting element, a yellow fluorescent member which absorbs a part of blue light from the blue-system semiconductor light emitting element and emits yellow-system light as excitation light, and a red fluorescent member which absorbs a part of green light from the green-system semiconductor light emitting element and emits red-system light as excitation light.

Claims

1. A white light source comprising:

a blue-yellow light-emitting section including a blue-system semiconductor light-emitting element and a sealing resin sealing the blue-system semiconductor light-emitting element, the sealing resin containing a yellow fluorescent member and being configured to emit yellow-system light by absorbing a part of blue light emitted from the blue-system semiconductor light-emitting element;

a red-green light-emitting section including a green-system semiconductor light-emitting element and a sealing resin sealing the green-system semiconductor light-emitting element, the sealing resin containing a red fluorescent member and being configured to emit red-system light by absorbing a part of green light emitted from the green-system semiconductor light-emitting element; and

a circuit board on which the blue-yellow light-emitting section and the red-green light-emitting section are adjacently disposed as independent sections.

2. The white light source according to claim 1,

wherein the blue-yellow light-emitting section and the red-green light emitting section are disposed. side-by-side with opposing side surfaces of the blue-yellow light-emitting section and the red-green light-emitting section in contact with each other.

3. The white light source according to claim 1,

wherein the blue-yellow light-emitting section and the red-green light-emitting section are disposed with a predetermined interval between opposing side surfaces of the blue-yellow light-emitting section and the red-green light-emitting section.

4. The white light source according to claim 1,

wherein the blue-yellow light-emitting section and the red-green light-emitting section are disposed with a light-shielding partition interposed between opposing side surfaces of the blue-yellow light-emitting section and the red-green light-emitting section.

5. The white light source according to claim 1,

wherein the red fluorescent member includes CaAlSiN₃ fluorescent particles in which Eu²⁺ is solid-solved.

6. An illumination apparatus comprising:

the white light source recited in claim 1; and

a circuit board on which the white light source is mounted.

7. An illumination apparatus comprising:

a plurality of white light sources, each of which is according to claim 1; and

a circuit board on which the plurality of the white light sources are mounted.

8. The white light source according to claim 1,

wherein the blue-system semiconductor light-emitting element is covered only by the sealing resin containing the yellow fluorescent member, and the green-system semiconductor light-emitting element is covered only be the sealing resin containing the red fluorescent member.

9. A white light source comprising:

a blue-yellow light-emitting section including a blue-system semiconductor light-emitting element and a sealing resin sealing the blue-system semiconductor light-emitting element, the sealing resin containing a yellow fluorescent member and being configured to emit yellow-system light by absorbing a part of blue light emitted from the blue-system semiconductor light-emitting element;

a red-green light-emitting section including a green-system semiconductor light-emitting element and a sealing resin sealing the green-system semiconductor light-emitting element, the sealing resin containing a red fluorescent member and being configured to emit red-system light by absorbing a part of green light emitted from the green-system semiconductor light-emitting element;

a circuit board on which the blue-yellow light-emitting section and the red-green light-emitting section are adjacently disposed as independent sections,

wherein the only sealing resin that covers said blue-system semiconductor light-emitting element is said sealing resin that contains a yellow fluorescent member and the only sealing resin that covers said green-system semiconductor light-emitting element is said sealing resin that contains a red fluorescent member.

10. The white light-source according to claim 9;

wherein the blue-yellow light-emitting section and the red-green light emitting section are disposed side-by-side with opposing side surfaces of the blue-yellow light-emitting section and the red-green light-emitting section in contact with each other.

11. The white light source according to claim 9,

wherein the blue-yellow light-emitting section and the red-green light-emitting section are disposed with a predetermined interval between opposing side surfaces of the blue-yellow light-emitting section and the red-green light-emitting section.

12. The white light source according to claim 9,

wherein the blue-yellow light-emitting section and the red-green light-emitting section are disposed with a light-shielding partition interposed between opposing side surfaces of the blue-yellow light-emitting section and the red-green light-emitting section.

13. The white light source according to claim 9,

wherein the red fluorescent member includes CaAlSiN₃ fluorescent particles in which Eu²⁺ is solid-solved.

14. An illumination apparatus comprising:

the white light source recited in claim 9; and

a circuit board on which the white light source is mounted.

15. An illumination apparatus comprising:

a plurality of white light sources, each of which is according to claim 9; and

a circuit board on which the plurality of the white light sources are mounted.