Compact optical assembly for LED light sources

Patent metadata

Field	Value
Publication number	US-10139078-B2
Application number	US-201514625926-A
Country	US
Kind code	B2
Filing date	Feb 19, 2015
Priority date	Feb 19, 2015
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

A compact optical assembly includes a linear array of LEDs, a plurality of reflectors, a plurality of lenses, and a cover. The reflectors include two reflecting surfaces that surround the LED light sources. One of the reflecting surfaces is defined by an arc of an ellipse that narrows into a throat in the axial direction away from the LED light source and cooperates with the other reflecting surface and the lens to create a collimated beam of light.

First claim

What is claimed:

1. A reflector for use in conjunction with an LED light source, said LED light source having an LED optical axis (A o ) centered on an area of light emission from which light is emitted in a hemispherical emission pattern surrounding said optical axis (A o ), said light consisting essentially of light emitted to one side of a first plane (P 1 ) coincident with said area of light emission and perpendicular to said optical axis (A o ), said reflector comprising:
a first reflecting surface and a second reflecting surface rotationally symmetrical about optical axis (A o ), said first reflecting surface extending from said first plane (P 1 ) and defined by an arc of an ellipse rotated about said optical axis (A o ), said ellipse having a first ellipse focus coincident with said area of light emission and a major axis canted relative to said optical axis (A o ), and said second reflecting surface defined by an arc of a parabola rotated about said optical axis (A o ) having a parabola focus axially spaced from said first reflecting surface and radially spaced from said optical axis (A o );
wherein said first reflecting surface and said second reflecting surface are configured to cooperate to redirect light rays divergent from said optical axis (A o ) into a direction substantially parallel with said optical axis (A o ).

2. The reflector of claim 1 , wherein the ellipse has a second focus axially spaced from said first plane (P 1 ), radially spaced from said optical axis (A o ), and coincident with said parabola focus.

3. The reflector of claim 1 , wherein said first reflecting surface has a first terminus at said first plane and a second terminus opposite said first terminus and wherein a diameter of said reflecting surface is larger at said first terminus than a diameter at said second terminus.

4. The reflector of claim 1 , further comprising a lens centered on said optical axis (A o ) and defined by a light entry surface and a light emission surface, wherein said light entry surface is configured to cooperate to redirect light divergent from said optical axis (A o ) into a direction substantially parallel with said optical axis (A o ).

5. The reflector of claim 1 , further comprising a transition surface extending from said first reflecting surface to said second reflecting surface.

6. The reflector of claim 5 , wherein said transition surface is defined by a conical sectional configuration between said first and second reflecting surfaces defined by a line rotated about said optical axis (A o ).

7. The reflector of claim 5 , wherein said transition surface is reflective to redirect light.

8. The reflector of claim 4 , wherein said light entry surface is defined by a hyperbolic sectional configuration centered on said optical axis (A o ) and rotated about said optical axis (A o ).

9. The reflector of claim 3 , wherein the second reflecting surface has a third terminus axially defined by the light ray reflected at said second terminus of said first reflecting surface.

10. The reflector of claim 3 , wherein the second reflecting surface has a fourth terminus axially defined by the light ray reflected at said first terminus of said first reflecting surface.

11. The reflector of claim 1 , wherein said major axis is canted between 10 and 50 degrees relative to said optical axis (A o ).

12. A beam forming optic for use in conjunction with an LED light source, said LED light source having an LED optical axis (A o ) centered on an area of light emission from which light is emitted in a hemispherical emission pattern surrounding said optical axis (A o ), said light consisting essentially of light emitted to one side of a first plane (P 1 ) coincident with said LED light source and perpendicular to said optical axis (A o ), said beam forming optic comprising:
a reflector rotationally symmetrical about optical axis (A o ) constructed from a first reflecting surface and a second reflecting surface, said first reflecting surface extending from said first plane (P 1 ) and defined by an arc of an ellipse rotated about said optical axis (A o ), said ellipse having a first ellipse focus coincident with said LED light source, a second ellipse focus axially spaced from said first plane (P 1 ) and radially spaced from said optical axis (A o ) and a major axis canted relative to said optical axis (A o ), and said second reflecting surface defined by an arc of a parabola rotated about said optical axis (A o ) having a parabola focus axially spaced from said first reflecting surface and radially spaced from said optical axis (A o ); and
a lens centered on said optical axis (A o ) and defined by a light entry surface and a light emission surface;
wherein said first reflecting surface, said second reflecting surface, and said light entry surface are configured to cooperate to redirect light rays divergent from said optical axis (A o ) into a direction substantially parallel with said optical axis (A o ).

13. The beam forming optic of claim 12 , wherein the second ellipse focus is coincident with said parabola focus.

14. The beam forming optic of claim 12 , wherein said first reflecting surface has a first terminus at said first plane and a second terminus opposite said first terminus and wherein a diameter of said reflecting surface is larger at said first terminus than a diameter at said second terminus.

15. The beam forming optic of claim 12 , further comprising a transition surface extending from said first reflecting surface to said second reflecting surface.

16. The beam forming optic of claim 15 , wherein said transition surface is defined by a generally conical sectional configuration between said first and second reflecting surfaces defined by a line rotated about said optical axis (A o ).

17. The beam forming optic of claim 12 , wherein said light entry surface is defined by a hyperbolic sectional configuration centered on said optical axis (A o ) and rotated about said optical axis (A o ).

18. The beam forming optic of claim 14 , wherein the second reflecting surface has a third terminus axially defined by the light ray reflected at said second terminus of said first reflecting surface.

19. The beam forming optic of claim 14 , wherein the second reflecting surface has a fourth terminus axially defined by the light ray reflected at said first terminus of said first reflecting surface.

20. The beam forming optic of claim 12 , wherein said major axis is canted between 10 and 50 degrees relative to said optical axis (A o ).

Assignees

• Whelen Eng

Inventors

• Shimoda Kyle

Classifications

• F21S41/336

  with discontinuity at the junction between adjacent areas · CPC title

• F21Y2115/10

  Light-emitting diodes [LED] · CPC title

• F21V7/06

  with parabolic curvature · CPC title

• F21S43/26

  Refractors, transparent cover plates, light guides or filters not provided in groups F21S43/235 - F21S43/255 · CPC title

• F21S41/28

  Cover glass · CPC title