Surface-mounted LED and light emitting device

• US 7,078,728 B2
• Filed: 07/27/2004
• Issued: 07/18/2006
• Est. Priority Date: 07/29/2003
• Status: Active Grant

• Current Assignee: Citizen Electronics Company Limited
• Original Assignee: Citizen Electronics Company Limited
• Inventors: Ishii, Hirohiko, Imai, Sadato
• Primary Examiner(s): TRAN, MAI HUONG C
• Application Number:
  US10/899,120
• Publication Number:
  US 20050023538A1
• Time in Patent Office: 721 Days
• Field of Search: 438/22, 438/82, 438/98, 438/106, 438/249, 257/79, 257/80, 257/432
• US Class Current: 257/79
• CPC Class Codes: H01L 2224/48091 Arched
• 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 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/64 Heat extraction or cooling elements

Abstract

A surface-mounted LED including a base having heat conductivity, an insulative wiring board fixed to the base and including a conductive pattern and a mounting hole, a light emitting element chip mounted on a mounting area exposed by the mounting hole of the wiring board, and a reflective frame having heat conductivity and fixed to the base and thermally coupled therewith, to surround the light emitting element chip, heat generation from the light emitting element chip being released through both the base and the reflective frame, or either one thereof.

Claims

1. A surface-mounted LED, comprising:

a base having heat conductivity;

an insulative wiring board fixed to said base and including conductive patterns and a mounting hole;

a light emitting element chip mounted on the base directly inside the mounting hole of the wiring board; and

a sealing member for sealing the light emitting element chip; and

a reflective frame having heat conductivity and fixed to the base within the mounting hole of the wiring board to surround the sealing member,

wherein the reflective frame is disposed separately from the sealing member, and

wherein heat generation from the light emitting element chip is released through both the base and the reflective frame.

2. The surface-mounted LED according to claim 1, wherein said light emitting element chip is connected with the conductive patterns of the wiring board through electrical connection members, and

wherein the conductive patterns include at ends thereof a plurality of electrical connection surfaces comprising terminal portions to supply a driving current for driving the light emitting element chip.

3. The surface-mounted LED according to claim 2, wherein the base is configured to release heat generated from the light emitting element chip to an outer surface of the base, and

wherein electrical connection surfaces are disposed on an upper surface of the base.

4. The surface-mounted LED according to claim 2, wherein said wiring board is disposed to extend from an upper surface and around both ends of the base to one portion of the lower surface of the base, and

wherein the electrical connection surfaces comprising the terminal portions are disposed to extend from an upper surface and around both ends of the base to a lower surface of the base.

5. The surface-mounted LED according to claim 1, wherein an inner surface of the reflective frame adjacent to the light emitting element chip includes a reflective surface to reflect light emitted from the light emitting element chip.

6. The surface-mounted LED according to claim 5, wherein a bright plating is provided on the reflective surface of the reflective frame.

7. A light emitting device, comprising:

the surface-mounted LED according to any one of claims 1 to 6;

further comprising a printed-circuit board including conductive patterns,

wherein said conductive patterns of the printed-circuit board and electrical connection surfaces provided on the surface-mounted LED being connected mechanically and electrically by a fixing structure.

8. The light emitting device according to claim 7, further comprising a heat release member having heat conductivity,

wherein said heat release member is fixed and thermally coupled with a peripheral portion of the reflective frame of the surface-mounted LED so that heat generated from the surface-mounted LED is released through the reflective frame and the heat release member.

9. The light emitting device according to claim 7, further comprising a heat release member having heat conductivity,

wherein the base includes a heat releasing part,

wherein said heat release member is fixed and thermally coupled with the heat releasing part of the base of the surface-mounted LED so that heat generated from the surface-mounted LED is released through the heat releasing part of the base and the heat release member.

10. The light emitting device according to claim 7, further comprising a first heat release member and a second heat release member which have heat conductivity,

wherein the base includes a heat releasing part,

wherein said first heat release member is fixed and thermally coupled with a peripheral portion of the reflective frame of the surface-mounted LED and said second heat release member is fixed and thermally coupled with the heat releasing part of the base of the surface-mounted LED so that heat generated from the surface-mounted LED is released through both the first heat release member and the second heat release member.