LED-array light source with aspect ratio greater than 1

Patent metadata

Field	Value
Publication number	US-9401103-B2
Application number	US-201213441558-A
Country	US
Kind code	B2
Filing date	Apr 6, 2012
Priority date	Feb 4, 2011
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

Abstract

An LED light source for use in LED lighting fixtures, the LED light source comprising a submount including an LED-populated area which has an aspect ratio greater than 1, an array of LEDs on the LED-populated area, and a lens on the submount over the LED-populated area. Various embodiments facilitating preferential-side lighting, such as for roadway uses, are also disclosed.

First claim

The invention claimed is:

1. An LED light source configured to direct LED-emitted light toward a preferential side, the light source comprising:
a submount including an LED-populated area which has an aspect ratio greater than 1 and major and minor orthogonal cross-dimensions, the preferential side being along the major cross-dimension;
an array of LEDs on the LED-populated area, the minor cross-dimension being defined by more than one LED; and
a lens on the submount over the LED-populated area.

2. The LED light source of claim 1 wherein the spacing and arrangement of the LEDs are such that the total LED area is at least about one-third of the LED-populated area.

3. The LED light source of claim 1 wherein the spacing and arrangement of the LEDs are such that the total LED area is at least about two-thirds of the LED-populated area.

4. The LED light source of claim 3 wherein the spacing and arrangement of the LEDs are such that the total LED area is about 90% of the LED-populated area.

5. The LED light source of claim 3 wherein the spacing between LEDs is no more than about 1 millimeter.

6. The LED light source of claim 5 wherein the spacing between LEDs is no more than about 0.5 millimeters.

7. The LED light source of claim 6 wherein the spacing between LEDs is no more than about 0.1 millimeters.

8. The LED light source of claim 7 wherein the spacing between LEDs is no more than about 0.075 millimeters.

9. The LED light source of claim 8 wherein the spacing between the LEDs is no more than about 0.05 millimeters.

10. The LED light source of claim 1 wherein the aspect ratio is at least about 1.25.

11. The LED light source of claim 10 wherein the aspect ratio is at least about 1.5.

12. The LED light source of claim 11 wherein the aspect ratio is at least about 2.

13. The LED light source of claim 1 wherein the LED-populated area is rectangular.

14. The LED light source of claim 13 wherein the array includes at least eight LEDs positioned in two rows of four LEDs in each row.

15. The LED light source of claim 13 wherein the array includes forty-eight LEDs positioned in four rows of twelve LEDs in each row.

16. The LED light source of claim 1 wherein the lens is shaped for refraction of LED-emitted light toward the preferential side.

17. The LED light source of claim 16 wherein the lens is asymmetric.

18. The LED light source of claim 1 wherein the lens is overmolded on the submount.

19. The LED light source of claim 1 wherein the submount comprises ceramic material.

20. The LED light source of claim 19 wherein the ceramic material is aluminum nitride.

21. The LED light source of claim 1 wherein the submount has front and back sides, the LED-populated area being on the front side, and the light source further comprises electrodes on the back side.

22. The LED light source of claim 1 wherein the LED-populated area is asymmetric.

23. An LED light source configured to direct LED-emitted light toward a preferential side, the LED light source comprising:
a submount including an LED-populated area which has an aspect ratio greater than 1;
an array of LEDs on the LED-populated area, the LED array defining an emitter axis; and
a lens on the submount over the LED-populated area, the lens having an outer surface and a centerline which is offset from the emitter axis toward the preferential side.

24. An LED light source configured to direct LED-emitted light toward a preferential side, the LED light source comprising:
a submount including an LED-populated area which has an aspect ratio greater than 1;
an array of LEDs on the LED-populated area, the LED-populated area having major and minor orthogonal cross-dimensions and the preferential side being along the major cross-dimension, the minor cross-dimension being defined by more than one LED, thereby providing an illumination pattern which is offset toward the preferential side with respect to the emitter axis; and
a lens on the submount over the LED-populated area.

25. An LED light source configured to direct LED-emitted light toward a preferential side, the LED light source comprising:
a submount including an LED-populated area with an array of light-emitting diodes (LEDs) thereon, the LED-populated area having first and second maximum cross-dimensions orthogonal to one another where the first cross-dimension is greater than the second cross-dimension, the second cross-dimension being defined by more than one LED, the preferential side being along the first cross-dimension; and
a lens on the submount over the LED-populated area.

26. The LED light source of claim 25 wherein the ratio of the first cross-dimension to the second cross-dimension of the LED-populated area is at least about 1.25.

27. The LED light source of claim 26 wherein the ratio is at least about 1.5.

28. The LED light source of claim 27 wherein the ratio is at least about 2.

29. The LED light source of claim 25 wherein the spacing and arrangement of the LEDs are such that the total LED area is at least about one-third of the LED-populated area.

30. The LED light source of claim 29 wherein the spacing and arrangement of the LEDs are such that the total LED area is at least about two-thirds of the LED-populated area.

31. The LED light source of claim 30 wherein the spacing and arrangement of the LEDs are such that the total LED area is about 90% of the LED-populated area.

32. The LED light source of claim 25 wherein the spacing between LEDs is no more than about 1 millimeter.

33. The LED light source of claim 32 wherein the spacing between LEDs is no more than about 0.5 millimeters.

34. The LED light source of claim 33 wherein the spacing between LEDs is no more than about 0.1 millimeters.

35. The LED light source of claim 34 wherein the spacing between LEDs is no more than about 0.075 millimeters.

36. The LED light source of claim 35 wherein the spacing between the LEDs is no more than about 0.05 millimeters.

37. The LED light source of claim 25 wherein the LED-populated area is rectangular.

38. The LED light source of claim 37 wherein the array includes at least eight LEDs positioned in two rows of four LEDs in each row.

39. The LED light source of claim 37 wherein the array includes forty-eight LEDs arranged in four rows of twelve LEDs in each row.

40. The LED light source of claim 25 being configured to refract LED-emitted light toward a preferential side.

41. The LED light source of claim 40 wherein the lens is shaped to direct LED-emitted light toward the preferential side.

42. The LED light source of claim 25 wherein the lens is overmolded on the submount.

43. The LED light source of claim 25 wherein the submount comprises ceramic material.

44. The LED light source of claim 43 wherein the ceramic material is aluminum nitride.

45. The LED light source of claim 25 wherein the submount has front and back sides, the LED-populated area being on the front side, and the light source further comprises electrodes on the back side.

46. The LED light

Assignees

• Wilcox Kurt S
• Keller Bernd
• Lowes Ted
• Andrews Peter S
• Cree Inc

Inventors

• Wilcox Kurt S
• Keller Bernd
• Lowes Ted
• Andrews Peter S

Classifications

• G09F9/33 Primary

  being semiconductor devices, e.g. diodes · CPC title

• G09F19/228

  Ground signs, i.e. display signs fixed on the ground · CPC title