Optical Waveguide and Luminaire Incorporating Same

• US 20160018584A1
• Filed: 09/25/2015
• Published: 01/21/2016
• Est. Priority Date: 01/30/2013
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Yuan, Zongjie, Wilcox, Kurt S., Tarsa, Eric J., Rol, Fabian Jean-Daniel, Ibbetson, James, Keller, Bernd P., Medendorp, Nicholas W. Jr.
• Granted Patent: US 9,823,408 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21K 9/61 using light guides
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 6/0021 for housing at least a part of the light source, e.g. by forming holes or recesses
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0035 provided on the surface of the light guide or in the bulk of it
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• CPC Class Codes: G02B 6/0041 provided in the bulk of the light guide
• CPC Class Codes: G02B 6/0043 provided on the surface of the light guide
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide
• CPC Class Codes: G02B 6/0058 varying in density, size, shape or depth along the light guide
• CPC Class Codes: G02B 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G02B 6/0088 of the light guide or other optical sheets in the package
• CPC Class Codes: G02B 6/009 of the light source in the package G02B6/0021 takes precedence

Abstract

An optical waveguide includes a body of optically transmissive material having a width substantially greater than an overall thickness thereof. The body of material has a first side, a second side opposite the first side, and a plurality of interior bores extending between the first and second sides each adapted to receive a light emitting diode. Extraction features are disposed on the second side and the extraction features direct light out of at least the first side and at least one extraction feature forms a taper disposed at an outer portion of the body.

Claims

1. An optical waveguide, comprising

a body of optically transmissive material having a width substantially greater than an overall thickness thereof and including a first side, a second side opposite the first side, an interior coupling cavity extending between the first and second sides and adapted to receive a light emitting diode, and extraction features on the second side;

wherein the extraction features direct light out of at least the first side and wherein at least one extraction feature has an extraction feature depth extending from the second side toward the first side that is between about 5% and about 75% of the overall thickness of the body of material and is defined by first and second surfaces that are disposed at different angles relative to the first side; and

wherein at least one extraction feature at least partially surrounds the interior coupling cavity.

2. The optical waveguide of claim 1, further including a light diverter extending into the interior coupling cavity for diverting light into and generally along the width of the body of material.

3. The optical waveguide of claim 2, wherein the light diverter comprises a symmetric reflective conical plug member that is circular in a dimension transverse to the width and thickness of the body of material.

4. The optical waveguide of claim 1, wherein the at least one extraction feature has one of an inverted V-shape that extends fully about the interior coupling cavity in a ring shape and a discrete prismatic shape.

5. The optical waveguide of claim 1, wherein the first side is substantially planar.

6. The optical waveguide of claim 1, wherein the body of material has a substantially circular shape in a dimension transverse to the width and thickness of the body of material and has an outer surface coaxial with the interior coupling cavity and wherein the extraction features are substantially circular in a dimension transverse to the width and thickness of the body of material, and symmetric about and coaxial with respect to the interior coupling cavity.

7. The optical waveguide of claim 1, wherein the interior coupling cavity comprises a central bore that extends fully through the body of material.

8. The optical waveguide of claim 7, wherein walls defining the central bore comprise equally-sized facets that are tapered with respect to the first and second sides of the body.

9. The optical waveguide of claim 2, in combination with an LED disposed in the central bore that directs incident light toward the light diverter.

10. The optical waveguide of claim 1, wherein a depth of the extraction features increases with distance from a center line of the waveguide body.

11. The optical waveguide of claim 1, wherein a spacing between extraction features increases overall with distance from a center line of the waveguide body.

12. The optical waveguide of claim 1, wherein the ring comprises a plurality of extraction features, each having a discrete prismatic shape.

13. An optical waveguide, comprising:

a body of optically transmissive material having a width substantially greater than an overall thickness thereof and including a first side, a second side opposite the first side, an interior coupling cavity extending between the first and second sides and adapted to receive a light emitting diode, and extraction features on the second side;

wherein the extraction features direct light out of at least the first side and wherein at least one extraction feature has an extraction feature depth extending from the second side toward the first side that is between about 5% and about 75% of the overall thickness of the body of material; and

wherein a spacing between extraction features increases overall with distance from a center line of the waveguide body.

14. The optical waveguide of claim 13, further including a light diverter extending into the interior coupling cavity for diverting light into and generally along the width of the body of material.

15. The optical waveguide of claim 13, wherein the light diverter comprises a symmetric reflective conical plug member that is circular in a dimension transverse to the width and thickness of the body of material.

16. The optical waveguide of claim 13, wherein at least one extraction feature has an inverted V-shape and extends fully about the interior coupling cavity.

17. The optical waveguide of claim 13, wherein the first side is substantially planar.

18. The optical waveguide of claim 13, wherein a depth of the extraction features increases with distance from a center line of the waveguide body.

19. The optical waveguide of claim 13, wherein the at least one extraction feature is defined by first and second surfaces that are disposed at different angles relative to the first side.

20. The optical waveguide of claim 13, wherein the interior coupling cavity comprises a central bore that extends fully through the body of material.