LED PACKAGE WITH CONVERGING EXTRACTOR

• US 20080012034A1
• Filed: 07/16/2007
• Published: 01/17/2008
• Est. Priority Date: 07/17/2006
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Barnes, Amy, Thielen, James, Ouderkirk, Andrew, Leatherdale, Catherine, Lu, Dong
• Application Number:
  US11/778,385
• Publication Number:
  US 20080012034A1
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: G02B 27/0972 Prisms prisms per se G02B5/04
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

In one aspect, the present application discloses a light source comprising an LED die optically coupled to an extractor comprising a plurality of optical elements each having a base, an apex smaller than the base, and a converging side extending between the base and the apex. The extractor base is no greater in size than the emitting surface of the LED die. In another aspect, methods of making light sources are disclosed, comprising the steps of providing an LED die having an emitting surface; forming a plurality of optical elements each having a base, an apex smaller than the base, and a converging side extending between the base and the apex; arranging the plurality of optical elements to form an extractor, the extractor having an extractor base no greater in size than the emitting surface; and optically coupling the extractor base to the emitting surface of the LED die.

Claims

1. A light source, comprising:

an LED die having an emitting surface; and

an extractor comprising a plurality of optical elements each having a base, an apex smaller than the base, and a converging side extending between the base and the apex, wherein the extractor has an extractor base no greater in size than the emitting surface, and wherein the extractor base is optically coupled to the emitting surface forming an interface between the extractor and the LED die.

2. The light source of claim 1, wherein the light source emits light in a side emitting pattern, wherein more than 50 percent of the emitted light is emitted at a polar angle greater than or equal to 45°

.

3. The light source of claim 2, wherein the side emitting pattern includes a plurality of side lobes.

4. The light source of claim 1, wherein the light source emits light in a side emitting pattern having a maximum intensity at a polar angle greater than or equal to 45°

.

5. The light source of claim 4, wherein the side emitting pattern includes a plurality of side lobes.

6. A light source of claim 1, wherein the base of each of the optical elements is greater than or equal to 10 μ

m in size.

7. The light source of claim 1, wherein the extractor base and the emitting surface are matched in size.

8. The light source of claim 1, wherein the extractor comprises a 2×

2 array of pyramidal shaped optical elements, wherein each of the optical elements has an index of refraction no greater than or equal to 1.75, and further wherein the extractor is bonded to the LED die at the emitting surface.

9. The light source of claim 8, further comprising an encapsulant material encapsulating the LED die and the extractor.

10. The light source of claim 8, wherein the extractor includes open portions for providing electrical contacts for the LED die.

11. The light source of claim 1, wherein the extractor comprises a land layer.

12. The light source of claim 1, wherein the extractor is bonded to the LED die at the emitting surface.

13. The light source of claim 1, wherein each of the optical elements has an index of refraction no greater than or equal to 1.75.

14. The light source of claim 1, wherein each of the optical elements comprises inorganic material.

15. The light source of claim 1, wherein the LED die is one of a plurality of LED dies arranged in an array.

16. The light source of claim 1, wherein the extractor includes open portions for providing electrical contacts for the LED die.

17. The light source of claim 1, further comprising an encapsulant material encapsulating the LED die and the extractor.

18. The light source of claim 1, wherein the apex is shaped as one of a point, a line, and a surface.

19. A method of making a light source, comprising the steps of:

providing an LED die having an emitting surface;

forming a plurality of optical elements each having a base, an apex smaller than the base, and a converging side extending between the base and the apex;

arranging the plurality of optical elements to form an extractor having an extractor base no greater in size than the emitting surface; and

optically coupling the extractor base to the emitting surface of the LED die.

20. The method of claim 19, wherein the forming step includes molding the optical elements.

21. The method of claim 20, wherein the arranging step includes leaving portions of the extractor open for providing electrical contacts for the LED die.

22. The method of claim 21, wherein the forming and arranging steps are performed simultaneously.

23. The method of claim 22, wherein the optically coupling step includes bonding the extractor base to the emitting surface of the LED die.

24. The method of claim 23, further comprising a step of encapsulating the LED die and the extractor with an encapsulant material.

25. The method of claim 19, wherein the arranging step includes leaving portions of the extractor open for providing electrical contacts for the LED die.

26. The method of claim 19, wherein the optically coupling step includes bonding the extractor base to the emitting surface of the LED die.

27. The method of claim 19, further comprising a step of encapsulating the LED die and the extractor with an encapsulant material.

28. A light source, comprising:

an LED die having an emitting surface;

an extractor comprising a plurality of optical elements each having a base, an apex smaller than the base, and a converging side extending between the base and the apex; and

an encapsulant material encapsulating the LED die and the extractor, wherein the extractor includes open portions for providing electrical contacts for the LED die,

wherein the extractor has an extractor base no greater in size than the emitting surface, wherein the extractor base is optically coupled to the emitting surface forming an interface between the extractor and the LED die, and wherein the extractor is bonded to the LED die at the emitting surface wherein the light source emits light in a side emitting pattern, and further wherein more than 50 percent of the emitted light is emitted at a polar angle greater than or equal to 45°

.