LED WITH LIGHT-CONVERSION LAYER

• US 20100117106A1
• Filed: 11/07/2008
• Published: 05/13/2010
• Est. Priority Date: 11/07/2008
• Status: Abandoned Application

• Current Assignee: Ledengin, Inc. (Ams-Osram AG)
• Original Assignee: Ledengin, Inc. (Ams-Osram AG)
• Inventors: TROTTIER, TROY A.
• Application Number:
  US12/267,512
• Publication Number:
  US 20100117106A1
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material

Abstract

A lighting apparatus includes a light-emitting diode (LED). A light-conversion layer having multiple non-overlapping regions overlies the light-emitting diode. The light-conversion layer includes at least one first region and at least one second region. In the lighting apparatus, the light-emitting diode is configured to emit light of a first color, the at least one first region is substantially transparent to light of the first color, and the at least one second region converts light of the first color to light of a second color. In an embodiment, the light-conversion layer is configured such that the lighting apparatus provides substantially uniform light of a third color. In some embodiments, the second region includes a phosphor-containing material, and the first region includes silicone or epoxy. In an example, the lighting apparatus uses a blue LED in conjunction with a yellow phosphor material to produce white light.

Claims

1. A lighting apparatus, comprising:

a light-emitting diode configured to emit light of a first color; and

a light-conversion layer overlying the light-emitting diode, the light-conversion layer including at least one first region that is substantially transparent to light of the first color and at least one second region that is configured to convert light of the first color to light of a second color.

2. The apparatus of claim 1 wherein the at least one second region comprises a phosphor-containing material.

3. The apparatus of claim 1 wherein the at least one first region comprises silicone or epoxy.

4. The apparatus of claim 1 wherein the at least one first region comprises a void in the light-conversion layer.

5. The apparatus of claim 1 wherein the at least one first region and at least one second region are arranged such that the lighting apparatus provides substantially uniform light of a third color.

6. The apparatus of claim 5 wherein the third color is white.

7. The apparatus of claim 6 wherein the first color is blue and the second color is yellow.

8. The apparatus of claim 5 wherein a ratio of areas of the at least one first region to the at least one second region is selected for providing light of the third color.

9. The apparatus of claim 1 wherein a thickness of the at least one second region is selected to maximize brightness of the light of the second color.

10. The apparatus of claim 1 wherein the light-conversion layer further comprises at least one third region that is configured to convert light of the first color to light of a third color.

11. The apparatus of claim 1 wherein the light-conversion layer is spaced apart from the light-emitting diode.

12. The apparatus of claim 1 wherein the light-conversion layer is in contact with the light-emitting diode.

13. The apparatus of claim 1 further comprising a lens overlying light-conversion layer, wherein the light-conversion layer is in contact with the lens.

14. The apparatus of claim 1 further comprising a substrate having a recess, wherein the light-emitting diode and the light conversion layer are disposed within the recess.

15. A method for making a lighting apparatus, the method comprising:

obtaining a light-emitting diode configured to emit light of a first color; and

forming a light-conversion layer overlying the light-emitting diode, the light-conversion layer having a plurality of non-overlapping regions including at least one wave-shifting region and at least one non-wave-shifting region,

wherein the at least one wave-shifting region is configured to convert at least a portion of incident light of the first color to light of a second color and the at least one non-wave-shifting region is substantially transparent to light of the first color,

wherein the light-conversion layer is configured to provide substantially uniform light of a third color.

16. The method of claim 15 wherein forming the light-conversion layer comprises:

forming a layer using a base material that is substantially transparent to light of the first color;

curing the layer of base material;

forming one or more voids in the base material; and

filling the one or more voids with a wave-shifting material.

17. The method of claim 16 wherein providing the light-emitting diode comprises:

providing a substrate having a recess; and

disposing the light-emitting diode in the recess,

wherein the layer of base material substantially fills the recess in the substrate.

18. The method of claim 16 wherein the base material includes a gel of silicone or an epoxy material.

19. The method of claim 15 wherein forming the light-conversion layer comprises:

forming a plate of a wave-shifting material, a thickness of the plate being selected for providing a predetermined conversion efficiency for producing light of the second color; and

forming one or more holes in the plate.

20. The method of claim 19 further comprising filling the holes with a base material that is substantially transparent to light of the first color.

21. The method of claim 15 wherein a ratio of areas of wave-shifting regions to non-wave-shifting regions is selected for providing substantially uniform white light.

22. The method of claim 15 wherein forming the light-conversion layer comprises:

providing a lens;

forming the light-conversion layer on a back surface of the lens; and

disposing the lens over the light-emitting diode.

23. The method of claim 15 wherein the light-conversion layer is formed on a top surface of the light-emitting diode.

24. A light conversion device, comprising:

a light-conversion layer having a plurality of non-overlapping regions including at least one wave-shifting region and at least one non-wave-shifting region,

wherein the at least one wave-shifting region is configured to convert light of a first color to light of a second color and the at least one non-wave-shifting region is substantially transparent to light of the first color.

25. The light conversion device of claim 24 wherein a thickness of the wave-shifting region is selected to maximize conversion efficiency for light of the second color.

26. The light conversion device of claim 24 wherein a ratio of areas of the wave-shifting region to the non-wave-shifting region is selected for providing light of a third color.

27. The light conversion device of claim 24 wherein a pattern of the wave-shifting region and the non-wave-shifting region is selected for providing substantially uniform light of the third color.

28. The light conversion device of claim 26 wherein the third color is white.

29. The light conversion device of claim 24 wherein the first color is blue and the second color is yellow.

30. The light conversion device of claim 24 wherein the at least one non-wave-shifting region comprises a void in the light-conversion layer.

31. A light conversion device, comprising:

a light-conversion layer having a plurality of non-overlapping regions including at least one region of a first type and at least one region of a second type,

wherein the at least one region of the first type is configured to convert incident light of a first color to light of a second color and the at least one region of the second type is configured to convert incident light of the first color to light of a third color that is different from the second color.

32. The light conversion device of claim 31 wherein the light-conversion layer further includes at least one region of a third type, wherein the at least one region of the third type is substantially transparent to incident light of the first color.

33. The light conversion device of claim 31 wherein a thickness of the at least one region of the first type is selected to maximize a conversion efficiency for converting incident light of the first color to light of the second color and wherein a thickness of the at least one region of the second type is selected to maximize a conversion efficiency for converting incident light of the first color to light of the third color.