Light source module with high heat-dissipation efficiency

• US 7,572,033 B2
• Filed: 09/18/2007
• Issued: 08/11/2009
• Est. Priority Date: 04/27/2007
• Status: Expired due to Fees

• Current Assignee: Foxsemicon Integrated Technology Incorporated
• Original Assignee: Foxsemicon Integrated Technology Incorporated
• Inventors: SUN, CHIH-HSIEN, CHANG, CHENG-WEI
• Primary Examiner(s): Alavi, Ali
• Application Number:
  US11/857,400
• Publication Number:
  US 20080266885A1
• Time in Patent Office: 693 Days
• Field of Search: 362/294, 362/373, 362/218, 362/547, 362/800, 361/703, 361/704, 361/707, 361/709, 257/713, 257/722
• US Class Current: 362/294
• CPC Class Codes: F21V 29/51 using condensation or evaporation of a fluid, e.g. heat pipes
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• 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: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 1/182 associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 7/205 Heat-dissipating body thermally connected to heat generating element via thermal paths through printed circuit board [PCB] details of PCBs relating to heat transfer H05K1/0201

Abstract

An exemplary light source module includes a printed circuit board (PCB), a heat-dissipating assembly, and a number of light emitting elements. The PCB includes a first surface, an opposite second surface, and a number of through holes. The heat-dissipating assembly is located adjacent to the second surface and includes a base, a number of heat-conducting elements, and a number of heat dissipation fins. The base includes a third surface defining a number of cavities therein and an opposite fourth surface. The heat dissipation fins extend from the fourth surface. Each of the heat-conducting elements is inlaid in a corresponding cavity. Each of the light emitting elements is placed in a corresponding through hole and thermally contacts a corresponding heat-conducting element. Each light emitting element electrically connects with the PCB and defines a respective light emitting surface located outside the corresponding through hole.

Claims

1. A light source module, comprising:

a printed circuit board including a first surface, a second surface opposite to the first surface, and a plurality of through holes penetrating through the first surface and the second surface;

a heat-dissipating assembly located adjacent to the second surface of the printed circuit board, the heat-dissipating assembly including a base, a plurality of heat-conducting elements, and a plurality of heat dissipation fins, the base defining a third surface and an opposite fourth surface, the third surface defining a plurality of cavities therein, the heat dissipation fins extending from the fourth surface and along a direction away from the third surface, each of the heat-conducting elements being inlaid in a corresponding cavity defined in the third surface, each of the heat-conducting elements thermally contacting with the base; and

a plurality of light emitting elements each being placed in a corresponding through holes of the printed circuit board and being thermally contacted with a corresponding heat-conducting elements, each of the light emitting elements being electrically connected with the printed circuit board, each of the light emitting elements defining a light emitting surface located outside the corresponding through hole and being directed away from the second surface of the printed circuit board.

2. The light source module of claim 1, wherein a surface of each of the heat-conducting elements that thermally contacted with the base is defined as a heat extraction surface, another surface of each of the heat-conducting elements that thermally contacted with a corresponding light emitting element is defined as a heat entry surface, and the heat extraction surface has an area larger than that of the heat entry surface.

3. The light source module of claim 2, wherein each of the heat extraction surfaces is arc-shaped.

4. The light source module of claim 2, wherein the heat extraction surface of each of the heat-conducting elements directly contacts with peripheral walls of a corresponding cavity.

5. The light source module of claim 2, wherein each of the heat-conducting elements thermally contacts with the base via a heat conductive material sandwiched between the heat extraction surface thereof and the peripheral walls of a corresponding cavity.

6. The light source module of claim 2, wherein the heat entry surface directly contacts a corresponding light emitting element.

7. The light source module of claim 2, wherein each of the heat-conducting elements thermally contacts a corresponding light emitting element via a thermal interface material interposed between the heat entry surface thereof and the corresponding light emitting element.

8. The light source module of claim 2, wherein each of the heat-conducting elements thermally contacts a corresponding light emitting element by metallurgically welding the heat entry surface thereof to a corresponding light emitting element.

9. The light source module of claim 2, wherein each of the heat-conducting elements is a hollow structure and is equipped with a wick structure formed in an internal sidewall near the heat entry surface thereof.

10. The light source module of claim 9, wherein each of the heat-conducting elements is at least one of a heat pipe and a vapor chamber.

11. The light source module of claim 2, wherein each of the light emitting elements is a point light source.

12. The light source module of claim 11, wherein the point light source is a light emitting diode lamp.

13. The light source module of claim 12, wherein the light emitting diode lamp is an SMD-type light emitting diode lamp, the SMD-type light emitting diode lamp further comprises a bottom surface opposite to the light emitting surface thereof, the bottom surface thermally contacts the heat entry surface of a corresponding heat-conducting element, and the first electrode and the second electrode thereof respectively extend along a direction substantially parallel to the bottom surface and away from each other.

14. The light source module of claim 13, wherein a distance between the bottom surface and the first electrode or the second electrode is substantially equal to a thickness of the printed circuit board along a direction oriented from the first surface thereof to the second surface thereof.

15. The light source module of claim 2, wherein the heat entry surface of each of the heat-conducting elements is located in a corresponding through hole of the printed circuit board.

16. The light source module of claim 2, wherein the heat entry surface of each of the heat-conducting element is substantially coplanar with the third surface of the base.

17. The light source module of claim 2, wherein each of the cavities defined in the third surface is arc-shaped.

18. A light source module, comprising:

a printed circuit board including a first surface, a second surface opposite to the first surface, and a plurality of through holes penetrating through the first surface and the second surface;

a heat-dissipating assembly located adjacent to the second surface of the printed circuit board, the heat-dissipating assembly including a heat-dissipating member, and a plurality of fluid-filled hollow structures, the heat-dissipating member defining a plurality of cavities therein, each of the fluid-filled hollow structures being inlaid in a corresponding cavity of the heat-dissipating member and having thermal contact therewith; and

a plurality of point light sources each being placed in a corresponding through holes of the printed circuit board, each point light source thermally contacting a corresponding fluid-filled hollow structure, each of the point light sources being electrically connected with the printed circuit board.

19. The light source module of claim 18, wherein each of the point light sources has a light emitting surface located outside of a corresponding through hole and directed away from the heat-dissipating assembly.

20. The light source module of claim 19, wherein a surface of each of the fluid-filled hollow structures that thermally contacted with the heat-dissipating member is defined as a heat extraction surface, another surface of each of the liquid-filled hollow structures that thermally contacted with a corresponding point light source is defined as a heat entry surface, and the heat extraction surface has an area larger than that of the heat entry surface.