Light emitting diode optical system and related methods

• US 8,616,733 B1
• Filed: 04/22/2009
• Issued: 12/31/2013
• Est. Priority Date: 04/22/2009
• Status: Active Grant

• Current Assignee: Tomar Electronics Incorporated
• Original Assignee: Tomar Electronics Incorporated
• Inventors: Millikan, Bart
• Primary Examiner(s): Han, Jason Moon
• Application Number:
  US12/428,253
• Time in Patent Office: 1,714 Days
• Field of Search: 362/249.02, 362/311.02, 362/800
• US Class Current: 362/311.02
• CPC Class Codes: F21V 5/045 the lens having discontinuous faces, e.g. Fresnel lenses
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A light emitting diode (LED) optical system. Implementations may include an LED coupled with a printed circuit board and an optic. The optic may include a first end and a second end opposing the first end. The optic may also include a first optical stage including the first end and a second optical stage including the second end. The first optical stage may include a total internal reflector and a second optical stage includes an upper reflector located at the second end. The optic may be coupled over the LED at the first end. The second optical stage may be configured to emulate a point light source for an outer lens coupled over the LED optical system using light emitted from the LED.

Claims

1. A light emitting diode (LED) optical system comprising:

an LED coupled with a circuit board; and

an optic comprising;

a first end and a second end, the second end opposing the first end; and

a first optical stage including the first end and a second optical stage including the second end;

wherein the first optical stage comprises a total internal reflector and has a rotationally symmetric cone-shaped portion coupled to a rotationally symmetric bowl-shaped portion and the second optical stage comprises an upper reflector located at the second end;

wherein the rotationally symmetric bowl-shaped portion is coupled around the LED at the first end; and

wherein the second optical stage is configured to emulate a point light source for an outer lens coupled over the LED optical system using light emitted from the LED.

2. The system of claim 1, wherein the LED is a Lambertian radiation pattern LED.

3. The system of claim 1, wherein the optic comprises an opening configured to receive the LED, wherein the opening tapers into the optic beyond an end of the rotationally symmetric bowl-shaped portion of the optic and into the rotationally symmetric cone-shaped portion of the first optical stage.

4. The system of claim 1, wherein the upper reflector is substantially cone-shaped and comprises a stack comprising at least one of aluminum, silver, gold, and chromium.

5. The system of claim 1, wherein the upper reflector is substantially cone-shaped and comprises a stack comprising at least one of a material with a higher index of refraction than a material included in the optic and a material with a lower index of refraction than a material included in the optic.

6. The system of claim 1, wherein the second optical stage is configured to produce a substantially lateral light pattern when the outer lens is coupled over the LED optical system.

7. The system of claim 6, wherein the outer lens is a Fresnel lens.

8. An optical system for a light emitting diode (LED), the optical system comprising an optic comprising:

a first end comprising a rotationally symmetric bowl-shaped portion with an opening therein configured to couple over an LED, the opening having a first bowl diameter, the opening centered within the rotationally symmetric bowl-shaped portion, wherein the rotationally symmetric bowl-shaped portion enlarges from the first bowl diameter to a second bowl diameter at a lip of the rotationally symmetric bowl-shaped portion opposing the opening; and

a second end opposing the first end, the second end comprising a rotationally symmetric cone-shaped portion physically coupled with the rotationally symmetric bowl-shaped portion at the lip, the rotationally symmetric cone-shaped portion having a first cone diameter substantially equal to the second bowl diameter and a second cone diameter smaller than the first cone diameter at a cone end opposing the rotationally symmetric bowl-shaped portion;

wherein the second end includes an upper reflector coupled at the cone end, the upper reflector having a diameter substantially equal to the second cone diameter.

9. The optical system of claim 8, wherein the opening in the rotationally symmetric bowl-shaped portion extends into the optic toward the second end of the optic beyond the lip.

10. The optical system of claim 9, wherein the opening comprises a second opening diameter at an end of the opening located beyond the lip, wherein the second opening diameter is smaller than the first bowl diameter and the opening tapers from the first bowl diameter to the second opening diameter.

11. The optical system of claim 8, wherein the upper reflector is substantially cone-shaped and comprises a stack comprising at least one of aluminum, silver, gold, and chromium.

12. The optical system of claim 8, wherein the upper reflector is substantially cone-shaped and comprises a stack comprising at least one of a material with a higher index of refraction than a material included in the optic and a material with a lower index of refraction than a material included in the optic.

13. The optical system of claim 8, further comprising a housing including an outer lens coupled over the optic and configured to emulate a point light source for the outer lens using light emitted from the LED.

14. The optical system of claim 13, wherein the optic system is configured to produce a substantially lateral light pattern when the outer lens is coupled over the LED optical system.

15. The optical system of claim 13, wherein the outer lens comprises a Fresnel lens.

16. An optical system for a light emitting diode (LED) comprising an optic comprising:

a rotationally symmetric cone-shaped portion of a first optical stage comprising a total internal reflector coupled to a rotationally symmetric bowl-shaped portion of the first optical stage; and

a second optical stage comprising an upper reflector, the upper reflector opposing an opening in the first optical stage;

wherein the rotationally symmetric bowl-shaped portion is configured to couple around an LED at the opening in the first optical stage; and

wherein the upper reflector has a diameter smaller than a largest diameter of the first optical stage.

17. The optical system of claim 16, further comprising an opening tapering into the first optical stage beyond an end of the rotationally symmetric bowl-shaped portion of the first optical stage into the rotationally symmetric cone-shaped portion of the first optical stage.

18. The optical system of claim 16, wherein the upper reflector is substantially cone-shaped and comprises a stack comprising at least one of aluminum, silver, gold, and chromium.

19. The optical system of claim 16, wherein the upper reflector is substantially cone-shaped and comprises a stack comprising at least one of a material with a higher index of refraction than a material included in the optic and a material with a lower index of refraction than a material included in the optic.

20. The optical system of claim 16, wherein the second optical stage is configured to produce a substantially lateral light pattern when a Fresnel lens is coupled over the LED optical system.

21. The optical system of claim 16, further comprising a housing including an outer lens coupled over the optic and configured to emulate a point light source for the outer lens using light emitted from the LED.

22. The optical system of claim 21, wherein the optic system is configured to produce a substantially lateral light pattern when the outer lens is coupled over the LED optical system.

23. The optical system of claim 22, wherein the outer lens comprises a Fresnel lens.

24. A method of distributing light from a light emitting diode (LED), the method comprising:

receiving light from an LED at a first end of an optic coupled over the LED;

focusing the light, using total internal reflection with a rotationally symmetric cone-shaped portion of the optic, onto an upper reflector included in a second end of the optic opposing the first end, wherein the upper reflector has a diameter smaller than a largest diameter of the first end and the rotationally symmetric cone-shaped portion is coupled to a rotationally symmetric bowl-shaped portion coupled around the LED; and

reflecting the light from the second end of the optic using the upper reflector.

25. The method of claim 24, further comprising emulating a point light source for an outer lens coupled over the LED and the optic using the upper reflector.

26. The method of claim 25, further comprising generating a substantially lateral light pattern with the outer lens and the light from the LED.