Optical waveguide assembly and light engine including same

Patent metadata

Field	Value
Publication number	US-9411086-B2
Application number	US-201314101099-A
Country	US
Kind code	B2
Filing date	Dec 9, 2013
Priority date	Jan 30, 2013
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

An optical waveguide assembly includes a plurality of separate body sections each having a coupling cavity for receiving an LED element and a light extraction feature spaced from the coupling cavity, and a mounting structure surrounding the plurality of body sections that maintains the plurality of body sections in assembled relationship. The waveguide assembly may be incorporated into a light engine.

First claim

We claim:

1. An optical waveguide assembly, comprising:
a plurality of separate body sections each comprising a coupling cavity for receiving an LED element and a light extraction feature spaced from the coupling cavity, wherein each body section comprises first and second curved walls disposed at an outer portion of the optical waveguide and that meet at an inflection portion spaced from another body section; and
a mounting structure surrounding the plurality of separate body sections that maintains the plurality of separate body sections in assembled relationship.

2. The optical waveguide assembly of claim 1 , further comprising an LED disposed in each coupling cavity.

3. The optical waveguide assembly of claim 1 , further comprising a plurality of LEDs disposed in each coupling cavity.

4. The optical waveguide assembly of claim 1 , wherein all of the body sections are shaped substantially identical to one another and each of the body sections is wedge-shaped.

5. The optical waveguide assembly of claim 4 , wherein each of the first and second curved walls comprises a continuously curved surface.

6. The optical waveguide assembly of claim 1 , wherein each body section comprises a plurality of light extraction features surrounding the coupling cavity.

7. The optical waveguide assembly of claim 6 , wherein the light extraction features of each body section are substantially identical to the plurality of light extraction features of other body sections.

8. The optical waveguide assembly of claim 7 , wherein the light extraction features of each body section are annular in shape.

9. The optical waveguide assembly of claim 8 , wherein the light extraction features of each body section are concentric with the coupling cavity of the body section.

10. The optical waveguide assembly of claim 1 , wherein the coupling cavity is defined by a plurality of side walls and a base wall.

11. The optical waveguide assembly of claim 10 , wherein the side walls are tapered and planar.

12. The optical waveguide assembly of claim 1 , wherein the mounting structure comprises a mounting ring secured to a base mounting surface.

13. The optical waveguide assembly of claim 12 , wherein the mounting structure comprises one of a specular reflective inner surface and a reflective white inner surface.

14. The optical waveguide assembly of claim 12 , wherein the base mounting surface is disposed in thermal communication with a heat exchanger.

15. The optical waveguide assembly of claim 14 , wherein LEDs are disposed on a circuit board disposed on the base mounting surface and extend into the coupling cavities.

16. The optical waveguide assembly of claim 1 , wherein each coupling cavity comprises at least one light coupling feature that extends into the respective body section.

17. The optical waveguide assembly of claim 1 , wherein each coupling cavity is disposed on one of an inner portion and an outer surface of the waveguide body section.

18. The optical waveguide assembly of claim 1 , wherein at least one waveguide body section comprises a plurality of coupling cavities.

19. The optical waveguide assembly of claim 1 , wherein each waveguide body section has a width substantially greater than an overall thickness thereof, and wherein the LED element extends into the coupling cavity transverse to the width of the waveguide body section.

20. The optical waveguide assembly of claim 19 , wherein the LED element extends into the waveguide coupling cavity at a non-zero angle relative to a central axis of the coupling cavity.

21. The optical waveguide assembly of claim 1 , wherein each waveguide body section has a width substantially greater than an overall thickness thereof and an edge surface and wherein the LED element extends into the waveguide body section from the edge surface.

22. The optical waveguide assembly of claim 21 , wherein the LED element has a central axis disposed at a non-zero angle relative to a lateral extent of the waveguide body section.

23. The optical waveguide assembly of claim 21 , wherein the LED element comprises first and second sets of LEDs wherein each LED of the first set comprises at least one LED of a first spectral emission characteristic and at least one LED of a second different spectral emission characteristic.

24. The optical waveguide assembly of claim 23 , wherein each LED of the first set comprises a blue-shifted yellow LED and each LED of the second set comprises a red LED, wherein the red LEDs are disposed between the blue-shifted yellow LEDs and wherein the blue-shifted yellow LEDs have a first height and the red LEDs have a second height different from than the first height, the LED element further comprising a lens disposed over the first and second sets of LEDs.

25. The optical waveguide assembly of claim 24 , wherein each LED is oriented such that the second set of LEDs is aligned approximately parallel to a central axis of the coupling cavity.

26. The optical waveguide assembly of claim 24 , wherein each LED is oriented such that the second set of LEDs is aligned approximately perpendicular to the central axis of the coupling cavity.

27. The optical waveguide assembly of claim 23 , wherein each LED of the first set comprises a blue-shifted yellow LED and each LED of the second set comprises a red LED, wherein the red LEDs and the blue-shifted yellow LEDs are disposed in a checkerboard pattern, the LED element further comprising a lens disposed over the first and second sets of LEDs.

28. A light engine, comprising:
an optical waveguide comprising
a plurality of body sections each of a wedge-shape and comprising a recess for receiving at least one LED and a plurality of curved light extraction features surrounding the recess, wherein each body section comprises first and second curved walls disposed at an outer portion of the optical waveguide and that meet at an inflection portion spaced from another body section;

a mounting structure surrounding the plurality of body sections that maintains the plurality of body sections in assembled relationship;
a base mounting surface; and
a plurality of LEDs disposed on a circuit board wherein the circuit board, the mounting structure, and assembled body sections are secured relative to the base mounting surface.

29. The light engine of claim 28 , further comprising a heat exchanger in thermal communication with the plurality of LEDs.

30. The light engine of claim 29 , wherein the base mounting surface is secured to the heat exchanger.

31. The light engine of claim 28 , wherein the mounting structure comprises specular reflective inner surfaces adjacent and at least substantially conforming to outer surfaces of the plurality of body sections.

32. The light engine of claim 31 , wherein each of the first and second curved walls comprises a continuously curved surface.

33. The light engine of claim 32 , wherein the recess of each body section is radially aligned with and proximate the inflection portion of the body section.

34. The light engine of claim 33 , wherein the extraction features of each body section are concentric with respect to the recess of such body section.

35. The light engine of claim 28 , wherein the recess is defined by a plurality of sidewalls and

Assignees

• Cree Inc

Inventors

• Yuan Zongjie
• Wilcox Kurt S
• Ma Jiayin

Classifications

• G02B6/0021

  for housing at least a part of the light source, e.g. by forming holes or recesses · CPC title

• G02B6/0016 Primary

  Grooves, prisms, gratings, scattering particles or rough surfaces · CPC title

• G02B6/0078

  Side-by-side arrangements, e.g. for large area displays · CPC title

• G02B6/0038

  Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide · CPC title

• G02F1/1335

  Structural association of cells with optical devices, e.g. polarisers or reflectors · CPC title