Lensed troffer-style light fixture

• US 9,874,322 B2
• Filed: 04/10/2012
• Issued: 01/23/2018
• Est. Priority Date: 04/10/2012
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Edmond, Mark D., Pickard, Paul Kenneth
• Primary Examiner(s): Hines, Anne
• Application Number:
  US13/443,630
• Publication Number:
  US 20130265751A1
• Time in Patent Office: 2,114 Days
• 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 8/04 intended only for mounting on a ceiling or the like overhead structures F21S8/02 takes precedence; details of ceiling bases F21V21/03
• CPC Class Codes: F21V 3/049 Patterns or structured surfaces for diffusing light, e.g. frosted surfaces
• CPC Class Codes: F21V 5/008 Combination of two or more successive refractors along an optical axis
• CPC Class Codes: F21V 7/005 with an elongated shape to cooperate with linear light sources
• CPC Class Codes: F21V 7/0083 Array of reflectors for a cluster of light sources, e.g. arrangement of multiple light sources in one plane combination of two or more reflectors F21V7/0025
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

Troffer-style lighting fixtures are disclosed having troffer housing with reflective regions, and respective light emitting diode (LED) arrays mounted in the reflective regions. The LED arrays are arranged to emit out of said troffer housing to illuminate a room below. The LED arrays can be driven by an elevated drive signal to produce a high luminous flux. The light fixtures according to the present invention can have lenses and diffusers over the arrays arranged to mix and disperse light from the light source to reduce hot spots and the appearance of individual LED colors. A plurality of first diffusers is included, each over a respective LED array. A second diffuser is included over the first diffusers, with the LED light passing through the diffusers prior to emitting from the lighting fixture. The diffusers can have shapes, surfaces or materials to disperse and/or mix the LED light as it emits.

Claims

1. A light fixture, comprising:

a fixture housing comprising a fixture opening;

at least three light emitting diode (LED) arrays mounted to said fixture housing, wherein at least two of said LED arrays are mounted to face substantially the same direction;

at least three first diffusers, each of said first diffusers over and at least partially surrounding at least one of said LED arrays, with each of said first diffusers dispersing and/or mixing light from its respective said LED array, wherein each of said first diffusers is mounted to said fixture housing, wherein a first and a second of said first diffusers are aligned in a first direction and said first and a third of said first diffusers are aligned in a second direction; and

at least one second diffuser, wherein light from at least one of said LED arrays passes through said second diffuser after passing through its respective one of said first diffusers.

2. The light fixture of claim 1, wherein said second diffuser covers at least a portion of said light fixture opening.

3. The light fixture of claim 1, wherein said second diffuser disperses and/or mixes light from said LED arrays.

4. The light fixture of claim 1, further comprising a plurality of reflective regions, at least one of said LED arrays in each of the reflective regions.

5. The light fixture of claim 4, wherein at least one of said first diffusers is in each of said reflective regions.

6. The light fixture of claim 1, wherein each of said LED arrays emit white light.

7. The light fixture of claim 1, wherein each of said LED arrays comprises a blue-shifted-yellow LED and a red LED.

8. The light fixture of claim 1, wherein said first diffuser has a hemispheric, bullet or globe shape.

9. The light fixture of claim 1, wherein said first diffuser is cylindrical shaped with tapered side surfaces.

10. The light fixture of claim 1, comprising a troffer-style light fixture.

11. The light fixture of claim 1, wherein said second diffuser completely covers said light fixture opening.

12. The light fixture of claim 1, wherein said second diffuser is planar.

13. The light fixture of claim 1, wherein a surface of said second diffuser is textured.

14. The light fixture of claim 1, wherein said second diffuser comprises a prismatic lens/diffuser.

15. The light fixture of claim 1, wherein said dispersed and/or mixed LED light from said first diffuser further mixes and reflects in said fixture housing before passing through said second diffuser.

16. The light fixture of claim 15, wherein said fixture housing comprises reflective sidewalls, wherein said dispersed and/or mixed LED light from said first diffuser reflects from said reflective sidewalls before passing through said second diffuser.

17. A light fixture, comprising:

a fixture housing comprising a fixture opening;

a plurality of solid state light sources mounted to said fixture housing;

a plurality of diffusers, wherein at least two of said diffusers are mounted with the same orientation with relation to said fixture opening, wherein said plurality of diffusers at least partially surround said plurality of light sources, the light from said plurality of light sources passing through said plurality of diffusers prior to emitting from said fixture housing, said diffusers dispersing and/or mixing light from said solid state light sources, wherein each of said diffusers is mounted to said fixture housing, wherein a first and a second of said plurality of diffusers are aligned in a first direction and said first and a third of said plurality of diffusers are aligned in a second direction.

18. The light fixture of claim 17, wherein said solid state light sources comprise an array of light emitting diodes (LEDs).

19. The light fixture of claim 17, wherein said plurality of diffusers comprises a plurality of first diffusers, each of which is over a respective one of said solid state light sources.

20. The light fixture of claim 19, wherein each of said first diffusers has a similar shape.

21. The light fixture of claim 19, further comprising a planar second diffuser.

22. The light fixture of claim 21, wherein said second diffuser comprises a prismatic diffuser.

23. The light fixture of claim 17, further comprising a plurality of reflective regions, at least one of said solid state light sources in each of the reflective regions.

24. The light fixture of claim 17, wherein each of said solid state light sources emits white light.

25. The light fixture of claim 17, wherein said first diffusers have a cylindrical, hemispheric, bullet or globe shape.

26. The light fixture of claim 17, comprising a troffer-style light fixture.

27. A troffer-style light fixture, comprising:

a troffer housing, comprising a plurality of reflective regions;

a plurality of light emitting diode (LED) light sources emitting white light, a respective one of which is mounted to said troffer housing in one of said reflective regions, wherein at least two of said LED light sources are mounted with the same orientation in relation to said troffer housing;

a plurality of first diffusers each of which is over and at least partially surrounding a respective one of said LED light sources, wherein each of said first diffusers is mounted to said troffer housing, wherein said plurality of first diffusers is in a grid formation; and

a second diffuser over said first diffusers, wherein light emitting from said fixture passes through said first and second diffuser for dispersing and/or mixing.

28. The troffer-style light fixture of claim 27, wherein each of said LED light sources comprises an LED array.

29. The troffer-style light fixture of claim 27, wherein each of said reflective regions comprises a diffuse reflective coating or layer.

30. The troffer-style light fixture of claim 27, wherein each of said reflective regions comprises a textured, diffuse, specular and semi-specular coating or layer.

31. The troffer-style light fixture of claim 27, wherein each of said first diffusers has a similar shape.

32. The troffer-style light fixture of claim 27, wherein said second diffuser is planar.

33. The troffer-style light fixture of claim 27, wherein said second diffuser comprises a prismatic diffuser.

34. The troffer-style light fixture of claim 27, sized to fit in a T-grad ceiling opening.

35. The troffer-style light fixture of claim 27, comprising an AC/DC converter providing a first DC signal to said light fixture and a plurality of DC/DC converters, each of which providing a second DC signal to a respective one of said LED light sources.

36. The troffer-style light fixture of claim 27, wherein said troffer housing has a troffer opening, said second diffuser in said troffer opening.

37. A light fixture, comprising:

a fixture housing comprising a fixture opening;

at least three light emitting diode (LED) arrays mounted to said fixture housing, wherein at least two of said LED arrays are mounted to face substantially the same direction;

at least three first diffusers, each of said first diffusers on and at least partially surrounding at least one of said LED arrays, with each of said diffusers dispersing and/or mixing light from its respective said LED array, wherein each of said first diffusers is mounted to said fixture housing, wherein said first diffusers are in a grid formation; and

at least one second diffuser on each of said first diffusers so that light from at least one of said LED arrays passes through said second diffuser after passing through said first diffusers.