Light-emitting device

• US 20020121645A1
• Filed: 03/05/2002
• Published: 09/05/2002
• Est. Priority Date: 03/05/2001
• Status: Active Grant

• Current Assignee: Sanken Electric Company Limited, Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Sanken Electric Company Limited, Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Tsukagoshi, Koji, Honda, Satoshi, Yasukawa, Takemasa, Yokota, Tsutomu, Omoya, Hideki
• Granted Patent: US 6,774,405 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• 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 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A light-emitting element is mounted in a cup-like portion formed on a substrate and a case. The cup-like portion is filled with a sealing member made of a light-transmissible resin. A layer made of a material having a refractive index lower than that of the sealing member is provided between the sealing member and a surface of the case.

Claims

1. A light-emitting device comprising:

a light-emitting element;

a case including a cup-like portion having a bottom on which said light-emitting element is mounted;

a sealing member with which said cup-like portion is filled so that said light-emitting element is covered with said sealing member; and

a low-refractive-index layer having a refractive index lower than that of said sealing member and formed between said sealing member and a surface of said case shaping a side surface of said cup-like portion.

2. A light-emitting device according to claim 1, wherein said low-refractive-index layer is made of a gap between said sealing member and said surface of said case.

3. A light-emitting device according to claim 2, wherein said gap has an end on an emission observation surface side, said end being filled with a light-transmissible material.

4. A light-emitting device according to claim 1, wherein, on the bottom side of said cup-like portion, said sealing member adheres to said surface of said case.

5. A light-emitting device according to claim 1, wherein said surface of said case is reflective.

6. A light-emitting device according to claim 1, wherein said sealing member is made of at least one material selected from the group consisting of silicone resin, epoxy resin, urea resin, and glass.

7. A light-emitting device according to claim 1, wherein said sealing member contains grains or fine particles of a light-transmissible material.

8. A light-emitting device according to claim 7, wherein said grains or fine particles are localized on the bottom side of said cup-like portion.

9. A light-emitting device according to claim 7, wherein said grains or fine particles have a linear expansion coefficient smaller than that of said sealing member.

10. A light-emitting device according to claim 1, wherein said sealing member contains a fluorescent substance.

11. A light-emitting device according to claim 1, further comprising a lens provided on the emission observation surface side of said light-emitting device.

12. A light-emitting device according to claim 1, wherein said sealing member has a surface on the emission observation surface side, said surface being shaped like a lens.

13. A light-emitting device according to claim 1, wherein the emission observation surface is covered with a light-transmissible material.

14. A light-emitting device according to claim 1, wherein said light-emitting element includes at least one Group III nitride compound semiconductor layer.

15. A light-emitting device comprising:

a light-emitting element;

a substrate or lead frame on which said light-emitting element is mounted; and

a sealing member with which said light-emitting element is covered, light emitted from said light -emitting element being partially reflected by a surface of said sealing member to thereby be radiated as light in a direction of an optical axis.