Illumination devices including multiple light emitting elements

• US 9,081,125 B2
• Filed: 02/01/2013
• Issued: 07/14/2015
• Est. Priority Date: 08/08/2011
• Status: Active Grant

• Current Assignee: Quarkstar LLC
• Original Assignee: Quarkstar LLC
• Inventors: Dau, Wilson, Gardner, Robert C., Lerman, George, Lerman, Louis, Lowery, Christopher H., Ogonowsky, Brian D., Smith, George E., Speier, Ingo, Steele, Robert V., Teng, Jacqueline, York, Allan Brent, Stormberg, Hans Peter
• Primary Examiner(s): BANNAN, JULIE A
• Application Number:
  US13/757,708
• Publication Number:
  US 20130208495A1
• Time in Patent Office: 893 Days
• 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 8/061 with a non-rigid pendant, i.e. a cable, wire or chain
• CPC Class Codes: F21V 2200/10 of light guides of the optical fibres type
• CPC Class Codes: F21V 2200/20 of light guides of a generally planar shape
• CPC Class Codes: F21V 23/003 the elements being electronics drivers or controllers for operating the light source, e.g. for a LED array
• CPC Class Codes: F21V 23/008 the casing being outside the housing of the lighting device
• CPC Class Codes: F21V 23/009 the casing being inside the housing of the lighting device
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 29/77 with essentially identical diverging planar fins or blades, e.g. with fan-like or star-like cross-section
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 7/0008 providing for indirect lighting
• CPC Class Codes: F21V 7/0025 Combination of two or more reflectors for a single light source array of reflectors for a cluster of light sources F21V7/0083
• CPC Class Codes: F21V 7/0041 for avoiding direct view of the light source or to prevent dazzling
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 1/045 Light guides
• CPC Class Codes: G02B 6/0025 Diffusing sheet or layer; Prismatic sheet or layer
• CPC Class Codes: G02B 6/0033 Means for improving the coupling-out of light from the light guide
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0045 by shaping at least a portion of the light guide
• CPC Class Codes: G02B 6/0046 : Tapered light guide, e.g. wedge-shaped light guide
• CPC Class Codes: G02B 6/005 : provided by one optical element, or plurality thereof, placed on the light output side of the light guide
• CPC Class Codes: G02B 6/0055 : Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0068 : Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0073 : Light emitting diode [LED]
• CPC Class Codes: G02B 6/0078 : Side-by-side arrangements, e.g. for large area displays

Abstract

A variety of illumination devices are disclosed that are configured to manipulate light provided by one or more light-emitting elements (LEEs). In general, embodiments of the illumination devices feature one or more optical couplers that redirect illumination from the LEEs to a reflector which then directs the light into a range of angles. In some embodiments, the illumination device includes a second reflector that reflects at least some of the light from the first reflector. In certain embodiments, the illumination device includes a light guide that guides light from the collector to the first reflector. The components of the illumination device can be configured to provide illumination devices that can provide a variety of intensity distributions. Such illumination devices can be configured to provide light for particular lighting applications, including office lighting, task lighting, cabinet lighting, garage lighting, wall wash, stack lighting, and downlighting.

Claims

1. An illumination device comprising:

one or more light-emitting elements (LEEs) operatively disposed on one or more substrates and configured to emit light in an emission angular range;

one or more primary optics optically coupled with the one or more LEEs and configured to direct light received from the one or more LEEs at one or more input ends of the one or more primary optics, and provide directed light in a collimated angular range at one or more output ends of the one or more primary optics, a divergence of the collimated angular range being smaller than a divergence of the emission angular range;

a light guide optically coupled at an input end of the light guide with the one or more output ends of the one or more primary optics, the light guide shaped to guide in a forward direction light received from the one or more primary optics to an output end of the light guide and provide guided light in a forward angular range at the output end of the light guide, wherein a prevalent direction of propagation within the forward angular range has a component parallel to the forward direction;

a solid secondary optic optically coupled with the second end of the light guide at an input end of the solid secondary optic to receive light from the light guide, the solid secondary optic having first and second redirecting surfaces and first and second output surfaces, the first and second redirecting surfaces being spaced apart from the input end of the secondary optic,

the first redirecting surface being configured to reflect at least a portion of light received at the input end of the solid secondary optic and provide the reflected light in a first backward angular range towards the first output surface, wherein a prevalent direction of propagation within the backward angular range has a component antiparallel to the forward direction, the solid secondary optic being configured to output the light reflected by the first redirecting surface as first output light in a first backward output angular range outside the solid secondary optic,

the second redirecting surface being configured to reflect at least a portion of the light received at the input end of the solid secondary optic and provide the reflected light in a second backward angular range towards the second output surface, the solid secondary optic being further configured to output the light reflected by the second redirecting surface as second output light in a second backward output angular range outside the solid secondary optic, and

the solid secondary optic being elongated orthogonally to the forward direction; and

an elongated secondary reflector facing the first output surface, wherein the elongated secondary reflector can be adjustably arranged and configured to reflect at least some of the first output light as third output light, and to provide the third output light in a first forward output angular range.

2. The illumination device of claim 1, wherein the elongated first secondary reflector is spaced apart from the first output surface.

3. The illumination device of claim 1, wherein the light guide comprises a light guide surface connecting the input end of the light guide with the output end of the light guide, and wherein one or more portions of the light guide comprise scattering centers that are configured to scatter some of the light from within the light guide through one or more portions of the light guide surface.

4. The illumination device of claim 3, wherein the scattering centers are disposed within the one or more portions of the light guide or on the light guide surface of the one or more portions of the light guide, and the scattering centers comprise at least one of (i) prisms, (ii) high reflectivity translucent contact points, or (iii) discontinuities in the light guide surface.

5. The illumination device of claim 1, wherein the light guide is deformable about a longitudinal extension of the light guide.

6. The illumination device of claim 1, wherein the light guide comprises two or more light guide elements.

7. The illumination device of claim 6, wherein the two or more light guide elements are arranged in parallel.

8. The illumination device of claim 6, wherein each light guide element comprises an input end and an output end, the input ends of the two or more light guide elements being coupled with the one or more output ends of the one or more primary optics, and the output ends of the two or more light guide elements being spaced apart.

9. The illumination device of claim 1, wherein the light guide comprises an input surface at the input end and an output surface at the output end, and wherein an area of the input surface is substantially the same as an area of the output surface.

10. The illumination device of claim 1, wherein the light guide comprises an input surface at the input end and an output surface at the output end, and wherein an area of the input surface is different from an area of the output surface.

11. The illumination device of claim 1, wherein the light guide comprises an input surface at the input end and an output surface at the output end, and wherein at least one of the input surface or the output surface comprise one or more discontinuities along a longitudinal dimension of the light guide.

12. The illumination device of claim 1, wherein the one or more substrates comprise two or more substrates and the one or more primary optics comprise two or more primary optics, each substrate being coupled with a primary optic from the two or more primary optics, wherein at least two of the two or more substrates are aligned within different planes and the light input end of the light guide is shaped to correspond to the output ends of the two or more primary optics.

13. The illumination device of claim 1, wherein the solid secondary optic further comprises a second output surface, the second output surface being arranged to output at least a portion of the light received at the input end of the solid secondary optic without being reflected by the redirecting surface.

14. The illumination device of claim 13, wherein the second output surface comprises a light conversion layer.

15. The illumination device of claim 1, wherein the secondary optic comprises two or more secondary optical elements, the two or more secondary optical elements being spaced apart, such that a portion of the guided light is output from the light guide in the third angular range.

16. The illumination device of claim 1, wherein the elongated secondary reflector comprises two or more reflector elements, the two or more reflector elements having spaced apart transparent portions through which light can be transmitted, wherein a position of the two or more reflector elements relative to each other is adjustable to vary an amount of the third output light relative to light transmitted through the transparent portions.

17. The illumination device of claim 16, wherein the transparent portions are openings.

18. The illumination device of claim 1, wherein at least one or more portions of the elongated secondary reflector comprise electrochromic material, wherein reflective properties of the electrochromic material are adjustable by applying an electrical charge to vary an amount of the third output light.

19. The illumination device of claim 1, wherein

a position of the elongated secondary reflector is adjustable along a length of the light guide between the input and output ends thereof, and

the illumination device is configured to vary the first forward angular range of the third output light by adjusting the position of the secondary reflector along the length of the light guide.

20. The illumination device of claim 1, wherein

a position of the elongated secondary reflector is adjustable about a pivot axis substantially orthogonal to the forward direction and parallel to a longitudinal extension of the light guide, and

the illumination device is configured to vary the first forward angular range of the third output light by adjusting the position of the elongated secondary reflector about the pivot axis.

21. The illumination device of claim 1, wherein an interface between the output end of the light guide and the solid secondary optic extends continuously along the output end of the light guide.

22. The illumination device of claim 1, wherein the LEEs comprise one or more light emitting diodes (LEDs).

23. The illumination device of claim 22, wherein the LEDs emit white light.

24. The illumination device of claim 1, wherein the light guide comprises a pair of side surfaces that are elongated in a direction orthogonal to the forward direction and extend from the input end to the output end of the light guide.

25. The illumination device of claim 1, wherein the side surfaces of the light guide are planar.