Optical arrangement for a solid-state lamp

• US 9,470,882 B2
• Filed: 04/25/2011
• Issued: 10/18/2016
• Est. Priority Date: 04/25/2011
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Lu, Dong
• Primary Examiner(s): Husar, Stephen F
• Assistant Examiner(s): ALLEN, DANIELLE NICOLE
• Application Number:
  US13/093,085
• Publication Number:
  US 20120268930A1
• Time in Patent Office: 2,003 Days
• Field of Search: 362 971- 974
• US Class Current: 1/1
• CPC Class Codes: F21K 9/233 specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps
• CPC Class Codes: F21V 5/007 Array of lenses or refractors for a cluster of light sources, e.g. for arrangement of multiple light sources in one plane combination of two or more refractors F21V5/008
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21V 5/10 comprising photoluminescent material
• CPC Class Codes: F21V 7/0083 Array of reflectors for a cluster of light sources, e.g. arrangement of multiple light sources in one plane combination of two or more reflectors F21V7/0025
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21V 7/26 the material comprising photoluminescent substances
• CPC Class Codes: F21V 7/28 characterised by coatings
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0066 in the form of an LED array
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

An optical arrangement for a solid-state lamp is disclosed. A highly reflective secondary reflector is located adjacent to but not in contact with an optical element. In some embodiments, the reflector presents a white, diffuse reflective surface. A secondary reflector with a specular reflective surface can also be used. The secondary reflector can be made of various commercially available materials; for example, MCPET or polycarbide resin, and the arrangement can be used with an LED light source. In some example embodiments, the optical element and the highly reflective secondary reflector each have a plurality of lobes and the arrangement is suitable for an MR16 halogen lamp replacement. In other example embodiments, the highly reflective secondary reflector includes a plurality of recesses corresponding to a plurality of optical elements, and the arrangement is suitable for a PAR incandescent bulb replacement.

Claims

1. An optical arrangement for a solid-state lamp, the optical arrangement comprising:

a total internal reflection (TIR) optical element including an outer surface with a conic shape that internally reflects light; and

a highly reflective secondary reflector, substantially conformal to, outside, and spaced a small gap away from the outer surface.

2. The optical arrangement of claim 1 wherein the highly reflective secondary reflector is spaced from a few micrometers to five mm away from the outer surface of the optical element.

3. The optical arrangement of claim 2 wherein the highly reflective secondary reflector is a diffuse white reflector.

4. The optical arrangement of claim 2 wherein the highly reflective secondary reflector is a specular reflector.

5. The optical arrangement of claim 3 wherein the highly reflective secondary reflector comprises thermoformable material.

6. The optical arrangement of claim 3 wherein the highly reflective secondary reflector comprises microcellular polyethylene terephthalate.

7. The optical arrangement of claim 3 wherein the highly reflective secondary reflector comprises polycarbide resin.

8. The optical arrangement of claim 3 wherein at least one of the TIR optical element and the highly reflective secondary reflector comprises a plurality of lobes.

9. The optical arrangement of claim 3 wherein the highly reflective secondary reflector comprises a plurality of recesses corresponding to a plurality of TIR optical elements.

10. The optical arrangement of claim 3 wherein the highly reflective secondary reflector comprises a surface having at least 85% reflectivity.

11. The optical arrangement of claim 10 wherein the highly reflective secondary reflector comprises a surface having at least 92% reflectivity.

12. The optical arrangement of claim 11 wherein the highly reflective secondary reflector comprises a surface having at least 95% reflectivity.

13. The optical arrangement of claim 12 wherein the highly reflective secondary reflector comprises a surface having at least 97% reflectivity.

14. A lamp comprising:

a light emitting diode (LED) light source;

a total internal reflection (TIR) optical element including an outer surface with a conic shape that internally reflects light from the LED light source; and

a highly reflective secondary reflector, substantially conformal to, outside, and spaced a small gap away from the outer surface.

15. The lamp of claim 14 wherein the highly reflective secondary reflector is spaced from a few micrometers to five mm away from the outer surface of the optical element.

16. The lamp of claim 15 wherein the LED light source comprises a plurality of LED packages arranged in an array.

17. The lamp of claim 16 wherein the highly reflective secondary reflector comprises microcellular polyethylene terephthalate.

18. The lamp of claim 16 wherein the highly reflective secondary reflector comprises polycarbide resin.

19. The lamp of claim 16 wherein at least one of the TIR optical element and the highly reflective secondary reflector comprises a plurality of lobes, wherein at least one lobe corresponds to each LED package.

20. The lamp of claim 19 further having a form factor of a standard halogen lamp.

21. The lamp of claim 20 wherein the highly reflective secondary reflector comprises a diffuse white surface having at least 85% reflectivity.

22. The lamp of claim 21 wherein the highly reflective secondary reflector comprises a diffuse white surface having at least 92% reflectivity.

23. The lamp of claim 22 wherein the highly reflective secondary reflector comprises a diffuse white surface having at least 95% reflectivity.

24. The lamp of claim 23 wherein the highly reflective secondary reflector comprises a diffuse white surface having at least 97% reflectivity.

25. The lamp of claim 16 further comprising:

a plurality of recesses in the highly reflective secondary reflector each associated with one of a plurality of TIR optical elements; and

a plurality of LED light sources, each corresponding to one of the plurality of recesses and one of the plurality of TIR optical elements.

26. The lamp of claim 25 further comprising;

a housing having a form factor of a standard incandescent bulb; and

an Edison base.

27. The lamp of claim 26 wherein the highly reflective secondary reflector comprises a diffuse white surface having at least 85% reflectivity.

28. The lamp of claim 27 wherein the highly reflective secondary reflector comprises a diffuse white surface having at least 92% reflectivity.

29. The lamp of claim 28 wherein the highly reflective secondary reflector comprises a diffuse white surface having at least 95% reflectivity.

30. The lamp of claim 29 wherein the highly reflective secondary reflector comprises a diffuse white surface having at least 97% reflectivity.

31. A method of assembling a lamp, the method comprising:

arranging a plurality of light emitting diode (LED) light sources in a pattern within a housing;

positioning a secondary reflector having at least 85% reflectivity near the plurality of LED light sources; and

placing at least one total internal reflection (TIR) optical element to receive light from at least one of the plurality of LED light sources so that a conically-shaped outer surface of the at least one TIR optical element reflects the light and is conformal to, inside, and spaced a small gap away from the secondary reflector.

32. The method of claim 31 wherein the at least one TIR optical element is spaced from a few micrometers to five mm away from the secondary reflector.

33. The method of claim 32 wherein at least one of the TIR optical element and the highly reflective secondary reflector comprises a plurality of lobes, wherein at least one lobe corresponds to each LED light source.

34. The method of claim 33 wherein the lamp has a form factor of a standard halogen lamp.

35. The method of claim 32 wherein the secondary reflector has plurality of recesses and wherein the placing of the at least one TIR optical element further comprises placing one TIR optical element in each recess of the plurality of recesses.

36. The method of claim 35 wherein the lamp has a form factor of a standard incandescent bulb with an Edison base.