LED lens

Patent metadata

Field	Value
Publication number	US-9410674-B2
Application number	US-201414462312-A
Country	US
Kind code	B2
Filing date	Aug 18, 2014
Priority date	Aug 18, 2014
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

A lens for primarily forward distribution of light from a light emitter which has an emitter axis in a front-to-back centerplane. The lens has a base surface which is adjacent the emitter and forms a light-entrance opening, an inner surface which defines a light-receiving cavity and includes front and back regions extending from the light-entrance opening, and an outer surface which has front and back regions adjoined by a middle region. The back region includes a back portion configured for forward total internal reflection (TIR) of rearward light received from the inner surface. The back portion extends transverse to the front-to-back centerplane away from the base surface from positions which are closer to the base surface than the innermost cavity region and terminates with a distal end which is closer to the base surface than outermost positions of the front region. The back portion terminates laterally at positions closer to the front-to-back centerplane than lateral edges of the light-entrance opening and, in the front-to-back centerplane, the emitter axis is no farther from the back portion of the outer surface than from a back edge of the light-entrance opening.

First claim

The invention claimed is:

1. A lens for primarily forward distribution of light from a light emitter which has an emitter axis in a front-to-back centerplane, comprising:
a base surface adjacent the emitter and forming a light-entrance opening;
an inner surface defining a light-receiving cavity extending from the light-entrance opening;
an outer light-output surface including front and back regions adjoined by a middle region together outlining the outer light-output surface adjacent to the base surface, the front region outlining lateral positions adjacent to the base surface which are farther from the front-to-back centerplane than lateral positions adjacent to the base surface outlined by the middle and back regions.

2. The lens of claim 1 wherein the distal end of the back surface portion is at positions closer to the base surface than outermost positions of the front region of the outer surface.

3. The lens of claim 1 wherein the back region of the outer surface comprises a back portion configured for forward total internal reflection (TIR) of rearward light received from the inner surface.

4. The lens of claim 1 wherein, in the front-to-back centerplane, the emitter axis is no farther from the back portion of the outer surface than from a back edge of the light-entrance opening.

5. The lens of claim 4 wherein the light-entrance opening is substantially circular.

6. The lens of claim 4 wherein the light emitter comprises at least one LED enclosed by a primary lens which has an outer surface shaped for primarily forward refraction of light from the at least one LED.

7. The lens of claim 6 wherein the outer surface of the primary lens is asymmetric in planes substantially parallel to the front-to-back centerplane.

8. A lens for primarily forward distribution of light from a light emitter which has an emitter axis in a front-to-back centerplane, comprising:
a base surface adjacent the emitter and forming a light-entrance opening;
an inner surface defining a light-receiving cavity extending from the light-entrance opening;
an outer surface including front and back regions adjoined by a middle region laterally bounding the back region along the base surface, the back region comprising a back portion which extends transverse the front-to-back centerplane away from the base surface such that, alone the front-to-back centerplane, the emitter axis is no farther from the back region than from the middle region, the back portion being configured for forward total internal reflection (TIR) of rearward light received from the inner surface.

9. The lens of claim 8 wherein the back portion of the back region is disposed in a recess defined by the middle region along the base surface.

10. The lens of claim 8 wherein the light emitter comprises at least one LED enclosed by a primary lens which has an outer surface shaped for primarily forward refraction of light from the at least one LED.

11. The lens of claim 10 wherein the outer surface of the primary lens is asymmetric in planes substantially parallel to the front-to-back centerplane.

12. The lens of claim 11 wherein the inner surface has front and back regions, the back inner-surface region having a substantially smooth cross-sectionally concave configuration.

13. The lens of claim 12 wherein:
the front region of the inner surface is substantially cross-sectionally convex along the light-entrance opening into the light-receiving cavity; and
the light-entrance opening is substantially circular.

14. The lens of claim 13 wherein the inner surface is substantially smooth.

15. The lens of claim 8 wherein lateral positions of the front region of the outer surface are farther from the front-to-back centerplane than lateral positions of the middle and back regions of the outer surface.

16. The lens of claim 15 wherein the back region of the outer surface comprises a distal end with the back portion extending rearwardly therefrom toward the base surface, the distal end being closer to the base surface than outermost positions of the front region of the outer surface.

17. The lens of claim 16 wherein the back region of the outer surface comprises a minor forward portion extending forwardly from the distal end to adjoining the middle region, the minor forward portion being positioned for receiving light reflected from the back portion and refracting the received light in a desired direction.

18. The lens of claim 17 wherein the front and middle regions of the outer surface have a substantially smooth configuration.

19. The lens of claim 8 further comprising a peripheral region extending radially outwardly from the light-entrance opening and including the base surface.

20. The lens of claim 19 wherein the peripheral region comprises a flange extending radially away from the outer surface.

21. A lens for primarily forward distribution of light from a light emitter which has an emitter axis in a front-to-back centerplane, comprising:
a base surface adjacent the emitter and forming a light-entrance opening;
an inner surface defining a light-receiving cavity and including front and back regions extending from the light-entrance opening to an innermost region of the cavity; and
an outer surface including front and back regions adjoined by a middle region, the back region of the outer surface comprising a back portion extending in a direction away from the base surface and terminates with a distal end which is closer to the base surface than outermost positions of the outer-surface front region, the back portion being configured for forward total internal reflection (TIR) of rearward light received from the inner surface.

22. The lens of claim 21 wherein
the back portion extends in a direction away from the base surface to a distal end from positions which are closer to the base surface than the innermost cavity region.

23. The lens of claim 22 wherein the back region comprises a minor forward portion extending from the distal end toward the emitter to adjoining the middle region, the minor forward portion positioned for receiving light reflected from the back portion.

24. The lens of claim 23 wherein the minor forward portion is configured for refraction of the received light in a desired direction.

25. The lens of claim 22 wherein the back portion of the back region is disposed in a recess defined by the middle region along the base surface.

26. The lens of claim 22 wherein the emitter axis is no farther from the back portion of the outer surface than from rearmost positions of the light-entrance opening along the back region of the inner surface.

27. The lens of claim 26 wherein the back region of the inner surface has a substantially smooth concave configuration.

28. The lens of claim 26 wherein the distal end of the back surface portion is at positions closer to the base surface than outermost positions of the front region of the outer surface.

29. The lens of claim 22 wherein the light emitter comprises at least one LED enclosed by a primary lens which has an outer surface shaped for primarily forward refraction of light from the at least one LED.

30. The lens of claim 21 wherein:
the back region of the outer surface comprises a minor forward portion positioned for receiving and refracting light reflected from the back portion, the minor forward portion

Assignees

• Cree Inc

Inventors

• Goldstein Corey
• Wilcox Kurt

Classifications

• H10W90/00

  Package configurations · CPC title

• H10H20/855

  Optical field-shaping means, e.g. lenses · CPC title

• G02B19/0061

  the light source comprising a LED · CPC title

• F21Y2101/02

  Mechanical Engineering · mapped topic

• F21V5/08

  producing an asymmetric light distribution · CPC title