SOLID STATE LAMP WITH THERMAL SPREADING ELEMENTS AND LIGHT DIRECTING OPTICS

• US 20110215345A1
• Filed: 02/16/2011
• Published: 09/08/2011
• Est. Priority Date: 03/03/2010
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Tong, Tao, TARSA, ERIC, Keller, Bernd, Letoquin, Ronan
• Granted Patent: US 10,359,151 B2
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: F21K 9/62 using mixing chambers, e.g. housings with reflective walls
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21V 29/00 Protecting lighting devices from thermal damage; Cooling or heating arrangements specially adapted for lighting devices or systems lighting fixtures combined with outlets for air-treatment systems F24F13/078
• CPC Class Codes: F21V 29/505 of reflectors
• CPC Class Codes: F21V 29/773 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21V 3/12 the coatings comprising photoluminescent substances
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details

Abstract

Lamps and bulbs are disclosed generally comprising different combinations and arrangements of a light source, one or more wavelength conversion materials, regions or layers which are positioned separately or remotely with respect to the light source, and a separate diffusing layer. This arrangement allows for the fabrication of lamps and bulbs that are efficient, reliable and cost effective and can provide an essentially omni-directional emission pattern, even with a light source comprised of a co-planar arrangement of LEDs. The lamps according to the present invention can also comprise thermal management features that provide for efficient dissipation of heat from the LEDs, which in turn allows the LEDs to operate at lower temperatures. The lamps can also comprise optical elements to help change the emission pattern from the generally directional (e.g. Lambertian) pattern of the LEDs to a more omni-directional pattern.

Claims

1. A solid state lamp, comprising:

a light emitting diode (LED);

an optical element over said LED such that light from said LED interacts with said optical element, said optical element changing the emission pattern of said LED to a broader emission pattern; and

a phosphor carrier over said optical element, said phosphor carrier converting at least some of said LED light to a different wavelength.

2. The lamp of claim 1, wherein said optical element comprises a substantially transparent material, light from said LED guided by said optical element into a broader emission pattern.

3. The lamp of claim 2, wherein said LED light is guided in said optical element by total internal reflection.

4. The lamp of claim 2, wherein said LED light is guided in said optical element by refraction.

5. The lamp of claim 2, wherein said optical element has a curved conical shape.

6. The lamp of claim 2, wherein a portion of said LED light is guided by said optical element to emit at an angle of 70 degrees or more to said LED.

7. The lamp of claim 2, wherein a portion of said LED light is guided by said optical element to emit at an angle of 80 degrees or more to said LED.

8. The lamp of claim 2, wherein a portion of said LED light is guided by said optical element to emit at an angle of 90 degrees or more to said LED.

9. The lamp of claim 2, wherein a portion of said LED light passes out of said optical element.

10. The lamp of claim 2, wherein said optical element has a three-dimensional shape.

11. The lamp of claim 1, wherein said optical element utilizes specular and/or scattering reflection to change said emission pattern of said LED to a broader emission pattern.

12. The lamp of claim 1, wherein said optical element comprises reflective surfaces, at least some of said LED light reflecting off said surfaces.

13. The lamp of claim 12, wherein said reflective surfaces are over said LED.

14. The lamp of claim 13, further comprising openings in said reflective surfaces to allow LED light to pass.

15. The lamp of claim 11, wherein said optical element is flower shaped.

16. The lamp of claim 15, wherein said optical element comprises one or more reflective blades over said LED, with light from said LED reflecting from said blades.

17. The lamp of claim 16, further comprising openings in said blades to allow LED light to pass.

18. The lamp of claim 16, further comprising spaces between said blades to allow LED light to pass.

19. The lamp of claim 1, further comprising a heat spreading substrate to spread heat from said LED prior to encountering heat resistant materials.

20. A solid state lamp, comprising:

a heat dissipation element;

a dielectric layer on said heat dissipation element;

a heat spreading substrate on said dielectric layer; and

a light emitting diode (LED) on and in thermal contact with said heat spreading substrate, said heat spreading substrate spreading heat from said LED prior to said LED heat reaching said dielectric layer.

21. The lamp of claim 20, wherein said heat spreading substrate comprises a high thermal conductivity material.

22. The lamp of claim 20, wherein said heat spreading substrate comprises a metal.

23. The lamp of claim 20, wherein said heat spreading substrate comprises copper or gold plated copper.

24. The lamp of claim 20, wherein said LED is mounted to said heat spreading substrate with a thermally conductive mechanism or material.

25. The lamp of claim 20, wherein said LED is mounted to said heat spreading substrate by a solder.

26. The lamp of claim 20, wherein said heat dissipation element comprises a heat sink.

27. The lamp of claim 20, further comprising an optical element to change the emission patter from said LED to a broader emission pattern.

28. The lamp of claim 20, further comprising a remote phosphor carrier.

29. The lamp of claim 21, further comprising a diffuser.

30. A solid state lamp, comprising:

a array of solid state emitters emitting light in a substantially directional emission pattern;

a three-dimensional optical element over said array of solid state light emitters, said optical element modifying the directional emission pattern of said array of solid state light emitters to a more omni-directional lamp emission pattern, with a portion of light from said solid state light emitters providing forward light emission for said lamp emission pattern.

31. The lamp of claim 30, wherein said array of solid state light emitters comprises an array of light emitting diodes (LEDs).

32. The lamp of claim 30, wherein said optical element comprises a substantially transparent material, light from said array of emitters guided through said optical element into said more omni-directional emission pattern.

33. The lamp of claim 32, wherein said array light is guided in said optical element by total internal reflection.

34. The lamp of claim 32, wherein said array light is guided in said optical element by refraction.

35. The lamp of claim 32, wherein said optical element has a curved conical shape.

36. The lamp of claim 30, wherein said array of light emitters is co-planar.

37. The lamp of claim 32, wherein a portion of said array light is guided by said optical element to emit at an angle of 70 degrees or more to said array of light emitters.

38. The lamp of claim 32, wherein a portion of said array light passes out the top surface of said optical element.

39. The lamp of claim 30, wherein said optical element utilizes specular and/or scattering reflection to change said emission pattern of said array of emitters to provide a broader emission pattern.

40. The lamp of claim 30, wherein said optical element comprises reflective surfaces, at least some of said array light reflecting off said surfaces.

41. The lamp of claim 40, wherein said reflective surfaces are over said LED.

42. The lamp of claim 41, further comprising openings in said reflective surfaces to allow array light to pass.

43. The lamp of claim 39, wherein said optical element is flower shaped.

44. The lamp of claim 43, wherein said optical element comprises one or more reflective blades over said array, with light from said array reflecting from said blades.

45. The lamp of claim 44, further comprising openings in said blades to allow array light to pass.

46. The lamp of claim 30, further comprising a heat spreading substrate to spread heat from said LED prior to encountering heat resistant materials.

47. The lamp of claim 30, further comprising phosphor carrier.

48. The lamp of claim 30, further comprising a diffuser.

49. The lamp of claim 30, sized to fit an A19 size profile.

50. The lamp of claim 30, comprising an emission pattern that is Energy Star compliant.

51. The lamp of claim 46, further comprising a fastener can serve the optical element to said heat spreading substrate 212.