Illumination assembly and method of making same

• US 20060131601A1
• Filed: 12/21/2004
• Published: 06/22/2006
• Est. Priority Date: 12/21/2004
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Wheatley, John A., Meis, Michael A., Ouderkirk, Andrew J., Schultz, John C., Tran, Hung T., Schenke, Kay-Uwe, Lehnhardt, Wolfgang N., Pojar, Stephen J.
• Application Number:
  US11/018,608
• Publication Number:
  US 20060131601A1
• Time in Patent Office: Days
• US Class Current: 257/99
• 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
• CPC Class Codes: H01L 2924/01004 Beryllium [Be]
• CPC Class Codes: H01L 2924/01012 Magnesium [Mg]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/642 characterized by the shape

Abstract

An illumination assembly including a thermally conductive substrate, a patterned conductive layer proximate a major surface of the thermally conductive substrate, a dielectric layer positioned between the patterned conductive layer and the major surface of the substrate, and at least one LED including a post that is attached to the major surface of the thermally conductive substrate is disclosed. The at least one LED can be thermally connected to the thermally conductive substrate through the post and electrically connected to the patterned conductive layer. The dielectric layer can be reflective.

Claims

1. An illumination assembly, comprising:

a thermally conductive substrate;

a patterned conductive layer proximate a major surface of the thermally conductive substrate;

a reflective dielectric layer positioned between the patterned conductive layer and the major surface of the substrate, wherein the reflective dielectric layer comprises at least one aperture; and

at least one LED comprising a post that is attached to the major surface of the thermally conductive substrate through the at least one aperture of the reflective dielectric layer, wherein the at least one LED is thermally connected to the thermally conductive substrate through the post and electrically connected to the patterned conductive layer.

2. The assembly of claim 1, wherein the reflective dielectric layer comprises multiple polymer layers of alternating refractive index.

3. The assembly of claim 1, wherein the thermally conductive substrate is also electrically conductive, and further wherein the at least one LED is electrically connected to the thermally and electrically conductive substrate through the post.

4. The assembly of claim 1, wherein the post comprises a threaded post, wherein the at least one LED further comprises an LED body, wherein the LED body is threaded onto the post.

5. The assembly of claim 1, wherein the at least one LED further comprises an LED body, wherein the LED body is friction-fit onto the post.

6. The assembly of claim 1, wherein the assembly comprises an array of LEDs.

7. The assembly of claim 1, wherein the assembly further comprises a thermally conductive adhesive positioned between tile post and the thermally conductive substrate.

8. The assembly of claim 1, wherein the at least one LED comprises a first electrode electrically connected to a first conductor of the patterned conductive layer and a second electrode electrically connected to a second conductor of the patterned conductive layer.

9. A method of making an illumination assembly, comprising:

providing a thermally conductive substrate;

forming a reflective dielectric layer on a major surface of the thermally conductive substrate;

forming a patterned conductive layer on the reflective dielectric layer;

providing at least one LED comprising a post; and

attaching the at least one LED to the thermally conductive substrate such that the at least one LED is thermally connected to the thermally conductive substrate through the post and electrically connected to the patterned conductive layer.

10. The method of claim 9, wherein attaching the at least one LED to the thermally conductive substrate comprises bonding the at least one LED to the thermally conductive substrate.

11. The method of claim 10, wherein bonding the at least one LED comprises ultrasonically welding the at least one LED to the thermally conductive substrate.

12. The method of claim 10, wherein bonding the at least one LED comprises soldering the at least one LED to the thermally conductive substrate.

13. The method of claim 10, wherein bonding the at least one LED comprises adhering the at least one LED to the thermally conductive substrate using a thermally conductive adhesive.

14. The method of claim 9, wherein attaching the at least one LED further comprises:

forming at least one aperture in the reflective dielectric layer; and

attaching the at least one LED to the thermally conductive substrate through the at least one aperture such that the post is in contact with the thermally conductive substrate.

15. The method of claim 14, wherein forming the at least one aperture comprises removing a portion of the reflective dielectric layer with the post.

16. The method of claim 9, wherein forming the reflective dielectric layer comprises attaching a polymeric multilayer optical film to the thermally conductive substrate.

17. The method of claim 9, wherein forming the reflective dielectric layer comprises coating the thermally conductive substrate with a reflective dielectric material.

18. The method of claim 9, wherein forming the patterned conductive layer comprises vapor depositing the patterned conductive layer on the reflective dielectric layer.

19. A display, comprising;

an illumination assembly, comprising;

a thermally conductive substrate;

a patterned conductive layer proximate a major surface of the thermally conductive substrate;

a reflective dielectric layer positioned between the patterned conductive layer and the major surface of the thermally conductive substrate, wherein the reflective dielectric layer comprises at least one aperture; and

at least one LED comprising a post that is attached to the major surface of the thermally conductive substrate through the at least one aperture of the reflective dielectric layer, wherein the at least one LED is thermally connected to the thermally conductive substrate through the post and electrically connected to the patterned conductive layer; and

a spatial light modulator optically coupled to the illumination assembly, wherein the spatial light modulator comprises a plurality of controllable elements operable to modulate at least a portion of light from the illumination assembly.

20. The display of claim 19, wherein the plurality of controllable elements of the spatial light modulator comprises liquid crystal display elements.