LED luminaire including a thin phosphor layer applied to a remote reflector

• US 9,316,368 B2
• Filed: 04/18/2011
• Issued: 04/19/2016
• Est. Priority Date: 04/18/2011
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Pickard, Paul Kenneth, Medendorp, Nicholas William Jr.
• Primary Examiner(s): Patel, Nimeshkumar
• Assistant Examiner(s): Lee, Brenitra M
• Application Number:
  US13/088,690
• Publication Number:
  US 20120262902A1
• Time in Patent Office: 1,828 Days
• Field of Search: 362/84
• US Class Current: 1/1
• CPC Class Codes: F21S 8/026 intended to be recessed in a ceiling or like overhead structure, e.g. suspended ceiling
• CPC Class Codes: F21S 8/03 of surface-mounted type F21S8/02, F21S8/04 take precedence; details of wall or floor bases F21V21/02
• CPC Class Codes: F21V 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 29/745 the fins or blades being planar and inclined with respect to the joining surface from which the fins or blades extend
• CPC Class Codes: F21V 29/75 with fins or blades having different shapes, thicknesses or spacing
• CPC Class Codes: F21V 29/777 the planes containing the fins or blades having directions perpendicular to the light emitting axis
• CPC Class Codes: F21V 7/0008 providing for indirect lighting
• CPC Class Codes: F21V 7/005 with an elongated shape to cooperate with linear light sources
• CPC Class Codes: F21V 7/24 characterised by the material
• CPC Class Codes: F21V 7/30 the coatings comprising photoluminescent substances
• CPC Class Codes: F21Y 2101/00 Point-like light sources
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

A luminaire including a thin phosphor layer applied to a remote reflector is disclosed. In some embodiments of the luminaire, LEDs illuminate and activate a thin remote phosphor coating applied to a reflective substrate. In some embodiments, the LED light source includes at least one LED with a GaN emitting layer. The LEDs can be packaged with or without a local phosphor. The thin remote phosphor can include red, red/orange, yellow, green or cyan emitting phosphor so that the luminaire produces white light. The thin remote phosphor layer can include two or more different color emitting phosphors. In some embodiments, the luminaire is a light fixture including a diffuser lens assembly and a pan to support the fixture when mounted in a ceiling.

Claims

1. A troffer comprising:

a reflector disposed to reflect light and direct light out of the troffer to provide illumination;

a plurality of LEDs to produce the light, the plurality of LEDs mounted on a surface to face the reflector;

a diffuser lens assembly disposed at the sides of the surface; and

a layer of phosphor between 5 and 50 μ

m thick applied to the reflector to provide wavelength conversion for at least a portion of the light from the light source;

wherein the surface faces a center region of the reflector to which the layer of phosphor is applied so that the troffer emits light through the diffuser lens assembly.

2. The troffer of claim 1 wherein the plurality of LEDs further comprises at least one LED with a GaN emitting layer.

3. The troffer of claim 2 wherein the layer of phosphor is between 5 and 25 μ

m thick.

4. The troffer of claim 2 wherein the plurality of LEDs comprise at least a first LED that is packaged as at least one of blue-shifted yellow (BSY), blue-shifted green (BSG), blue-shifted red (BSR), blue, and cyan-shifted red (CSR) LED devices.

5. The troffer of claim 4 wherein the layer of phosphor includes at least one of red, red/orange, yellow, green and cyan emitting phosphor so that the light emitted through the diffuser lens assembly comprises substantially white light.

6. The troffer of claim 5 further comprising:

a pan surrounding the diffuser lens assembly to support the troffer when mounted in a ceiling.

7. The troffer of claim 6 wherein the layer of phosphor includes at least two, different color emitting phosphors.

8. The troffer of claim 4 wherein the plurality of LEDs further comprises at least a second LED that emits one of blue, royal blue and cyan light.

9. The troffer of claim 8 wherein the layer of phosphor includes at least one of red, red/orange, yellow, green and cyan emitting phosphor.

10. The troffer of claim 9 further comprising:

a pan surrounding the diffuser lens assembly to support the troffer when mounted in a ceiling.

11. The troffer of claim 10 wherein the layer of phosphor includes at least two, different color emitting phosphors.

12. A light fixture comprising:

a reflector disposed to reflect light and direct light out of the light fixture;

a plurality of GaN LED devices to produce the light, at least some of the plurality of GaN devices mounted on a surface to face the reflector;

a phosphor applied to the reflector to provide wavelength conversion for at least a portion of the light from the plurality of GaN LED devices; and

a diffuser lens assembly through which light exits the light fixture, the diffuser lens assembly disposed at the sides of the surface;

wherein the surface faces a center region of the reflector to which the phosphor is applied so that the light fixture emits light through the diffuser lens assembly.

13. The light fixture of claim 12 wherein the plurality of GaN LED devices comprises at least a first LED that is one of a blue-shifted yellow (BSY), blue-shifted green (BSG), blue-shifted red (BSR), blue and cyan-shifted red (CSR) LED device so that the light emitted through the diffuser lens assembly comprises substantially white light.

14. The light fixture of claim 13 wherein the phosphor includes at least one of red, red/orange, yellow, green and cyan emitting phosphor.

15. The luminaire of claim 14 wherein the thin layer of phosphor includes at least two, different color emitting phosphors.

16. The light fixture of claim 14 further comprising a heatsink on which the GaN LED devices are mounted.

17. The light fixture of claim 16 wherein the diffuser lens assembly comprises two lens plates.

18. The light fixture of claim 17 wherein the reflector comprises two parabolic regions.

19. The light fixture of claim 17 wherein the reflector comprises a flat region opposite the heatsink.

20. The light fixture of claim 14 wherein the plurality of GaN LED devices further comprise at least a second LED device that emits one of blue, royal blue and cyan light.

21. The light fixture of claim 20 further comprising a heatsink on which the GaN LED devices are mounted.

22. The light fixture of claim 21 wherein the diffuser lens assembly comprises two lens plates disposed at the sides of the heatsink.

23. The light fixture of claim 22 wherein the reflector comprises two parabolic regions.

24. The light fixture of claim 22 wherein the reflector comprises a flat region opposite the mounting surface of the heatsink.

25. A method of assembling a light fixture, the method comprising:

providing a housing including a reflector;

coating the reflector with a phosphor to a thickness of from 5 to 50 μ

m;

installing a plurality of GaN LEDs on a mounting surface of a heatsink wherein the mounting surface faces a center region of the reflector coated with the phosphor so that light from the plurality of GaN LEDs impinges on the reflector with the phosphor; and

positioning a diffuser lens assembly adjacent to the heatsink so that light from the plurality of GaN LEDs is reflected from the reflector with the phosphor and leaves the light fixture through the diffuser lens assembly.

26. The method of claim 25 wherein the reflector is coated with phosphor to a thickness of from 5 to 25 μ

m.

27. The method of claim 25 further comprising connecting a pan to the housing in order to support the light fixture when mounted in a ceiling.

28. The method of claim 27 wherein the positioning of the diffuser includes positioning two lens plates at the sides of the heatsink.

29. The method of claim 26 further comprising connecting a pan to the housing in order to support the light fixture when mounted in a ceiling.

30. The method of claim 29 wherein the positioning of the diffuser includes positioning two lens plates at the sides of the heatsink.

31. A lighting system comprising:

an LED on a mounting surface; and

a layer of remote phosphor between 5 and 50 μ

m thick;

wherein the LED and the remote phosphor are selected and positioned with the mounting surface facing a central region of the remote phosphor so that indirect light is provided and is emitted from the lighting system through a diffuser lens assembly disposed at the sides of the mounting surface adjacent to the LED.

32. The lighting system of claim 31 wherein the remote phosphor is applied to a reflector disposed to reflect the light from the LED through the diffuser lens assembly.

33. The lighting system of claim 32 wherein the LED further comprises at least one LED with a GaN emitting layer.

34. The lighting system of claim 33 wherein the remote phosphor is between 5 and 25 μ

m thick.

35. The lighting system of claim 33 wherein the remote phosphor comprises at least two, different color emitting phosphors so that the light emitted through the diffuser lens assembly comprises substantially white light.