Thermal Energy Dissipating and Light Emitting Diode Mounting Arrangement

• US 20100237364A1
• Filed: 03/19/2010
• Published: 09/23/2010
• Est. Priority Date: 03/19/2009
• Status: Abandoned Application

• Current Assignee: CID Technologies LLC
• Original Assignee: CID Technologies LLC
• Inventors: Christy, Alexander C.
• Application Number:
  US12/727,994
• Publication Number:
  US 20100237364A1
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21V 17/04 the fastening being onto or by the light source
• CPC Class Codes: F21V 29/54 using thermoelectric means, e.g. Peltier elements
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/773 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 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• 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

Abstract

A thermal energy dissipating and LED mounting arrangement includes a plurality of LEDs and a thermally conductive sheet. The thermally conductive sheet has a length, a width and a thickness, and defines a plurality of openings through the thickness. Each of the plurality of openings is sized to receive and securely hold therein a different one of the plurality of LEDs such that the thermally conductive sheet defining the opening is in physical, thermally conductive contact with an exterior surface of at least one side portion of encapsulating material surrounding a corresponding one of the plurality of LEDs. The thermally conductive sheet carries the plurality of LEDs, and also absorbs thermal energy generated within each of the plurality of LEDs as a result of current flow through the LED circuit and rejects the absorbed thermal energy to an ambient environment surrounding the thermally conductive sheet.

Claims

1. A thermal energy dissipating and light emitting diode (LED) mounting arrangement, comprising:

a plurality of LEDs each including an LED circuit having a top surface from which radiation is emitted in response to current flow through the LED circuit and an opposite bottom surface mounted to a mounting surface, and encapsulating material surrounding the LED circuit and the mounting surface, the encapsulating material defining a top portion opposite the top surface of the LED circuit, a bottom portion opposite the mounting surface and at least one side portion extending between the bottom portion and the top portion, and

a thermally conductive sheet having a length, a width and a thickness, the thermally conductive sheet defining a plurality of openings through the thickness, each of the plurality of openings sized to receive and securely hold therein a different one of the plurality of LEDs such that the thermally conductive sheet defining the opening is in physical, thermally conductive contact with an exterior surface of the at least one side portion of the encapsulating material of a corresponding one of the plurality of LEDs, the thermally conductive sheet carrying the plurality of LEDs, and also absorbing thermal energy generated within each of the plurality of LEDs as a result of current flow through the LED circuit and rejecting the absorbed thermal energy to an ambient environment surrounding the thermally conductive sheet.

2. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the plurality of LEDs comprise an m×

n array of LEDs arranged on the thermally conductive sheet, where m and n are positive integers and where m>

1 and n>

1.

3. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the plurality of LEDs comprise a p×

1 array of LEDs arranged on the thermally conductive sheet, where p is a positive integer and p>

1.

4. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the thermally conductive sheet comprises copper (Cu).

5. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the thermally conductive sheet comprises aluminum (Al).

6. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the thermally conductive sheet comprises one or more of copper (Cu), Aluminum (Al), Gold (Au), Silver (Au), Magnesium (Mg), Tin (Sn), Zinc (Zn), Tungsten (W) and Beryllium (Be).

7. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the thermally conductive sheet is formed of a material having a thermal conductivity of at least 50 W/mK.

8. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the thermally conductive sheet is formed of a material having a thermal conductivity of at least 200 W/mK.

9. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the thermally conductive sheet is separate from, and is not connected to, the mounting surface.

10. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the thermally conductive sheet is electrically isolated from the semiconductor circuit.

11. The thermal energy dissipating and LED mounting arrangement of claim 1 further comprising a high surface emissivity coating applied to one or more surfaces of the thermally conductive sheet.

12. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein an interface is defined between each of the plurality of openings defined through the thickness of the thermally conductive sheet and the at least one side of the encapsulating material of a corresponding one of the plurality of LEDs,

and further comprising a thermally conductive medium interposed in each of the interfaces, the thermally conductive medium facilitating transfer of the thermal energy from each of the plurality of LEDs to the thermally conductive sheet.

13. The thermal energy dissipating and LED mounting arrangement of claim 12 wherein the thermally conductive medium comprises at least one of a thermally conductive grease and a thermally conductive bonding medium.

14. The thermal energy dissipating and LED mounting arrangement of claim 1 wherein the LED circuit defines a semiconductor junction between the top and bottom surfaces thereof across which the current flows through the LED circuit, the semiconductor junction defining a plane that is substantially parallel with the top and bottom surfaces of the LED circuit.

15. The thermal energy dissipating and LED mounting arrangement of claim 14 wherein the thickness of the thermally conductive sheet is substantially aligned with the plane defined by the semiconductor junction of the LED circuit of each of the plurality of LEDs.

16. The thermal energy dissipating and LED mounting arrangement of claim 14 wherein the thickness of the thermally conductive sheet defining each of the plurality of openings intersects an angle of less than or equal to a predefined angle relative to the plane defined by the semiconductor junction of the LED circuit of a corresponding one of the plurality of LEDs.

17. The thermal energy dissipating and LED mounting arrangement of claim 16 wherein the predefined angle is about 60 degrees.

18. The thermal energy dissipating and LED mounting arrangement of claim 16 wherein the predefined angle is about 45 degrees.

19. The thermal energy dissipating and LED mounting arrangement of claim 16 wherein the predefined angle is about 15 degrees.

20. The thermal energy dissipating and LED mounting arrangement of claim 16 wherein the predefined angle is about zero degrees such that the plane defined by the semiconductor junction of the LED circuit of each of the plurality of LEDs substantially bisects the thickness of the thermally conductive sheet.