LED based pedestal-type lighting structure

• US 9,217,544 B2
• Filed: 08/29/2013
• Issued: 12/22/2015
• 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, LeToquin, Ronan, Keller, Bernd, Lowes, Theodore, Tarsa, Eric, Youmans, Mark
• Primary Examiner(s): Green, Tracie Y
• Application Number:
  US14/014,272
• Publication Number:
  US 20140003048A1
• Time in Patent Office: 845 Days
• Field of Search: 313/46, 313/498, 313/148, 313/512, 297/40, 297/269, 362/294, 362/365
• US Class Current: 1/1
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• 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 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• 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 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21V 3/04 characterised by materials, surface treatments or coatings
• CPC Class Codes: F21Y 2107/00 Light sources with three-dimensionally disposed light-generating elements
• CPC Class Codes: F21Y 2107/40 on the sides of polyhedrons, e.g. cubes or pyramids
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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
• CPC Class Codes: H01L 2924/181 Encapsulation

Abstract

LED based lamps and bulbs are disclosed that comprise a pedestal having a plurality of LEDs, wherein the pedestal at least partially comprises a thermally conductive material. A heat sink structure is included with the pedestal thermally coupled to the heat sink structure. A remote phosphor is arranged in relation to the LEDs so that at least some light from the LEDs passes through the remote phosphor and is converted to a different wavelength of light. Some lamp or bulb embodiments can emit a white light combination of light from the LEDs and the remote phosphor. These can include LEDs emitting blue light with the remote phosphor having a material that absorbs blue light and emits yellow or green light. A diffuser can be included to diffuse the emitting light into the desired pattern, such as omnidirectional.

Claims

1. A light emitting diode (LED) based bulb, comprising:

an elongated pedestal comprising multiple surfaces, wherein said pedestal comprises a top surface and at least one side surface such that said at least one side surface has an angle greater than 90 degrees to said top surface;

a plurality of LEDs, each of which can be mounted to one of said surfaces, said pedestal comprising a thermally conductive path to conduct heat away from said LEDs; and

a diffuser arranged in relation to said LEDs so that light from said LEDs passes through said diffuser, with said diffuser modifying the emission pattern of said LEDs producing the desired bulb emission pattern.

2. The bulb of claim 1, wherein said diffuser modifies the emission pattern of said LED into an omnidirectional pattern.

3. The bulb of claim 1, wherein said diffuser comprises a diffuser dome.

4. The bulb of claim 1, further comprising a shaped phosphor arranged remote to said LEDs so that at least some light from said LEDs passes through said remote phosphor and is converted to a different wavelength of light.

5. The bulb of claim 1, further comprising a heat sink structure wherein said thermally conductive path is thermally coupled to said heat sink structure.

6. The bulb of claim 5, further comprising a remote phosphor mounted to said heat sink structure with heat from said remote phosphor conducting to said heat sink.

7. The bulb of claim 1, wherein said pedestal at least partially comprises a thermally conductive material.

8. The bulb of claim 1, comprising multiple side surfaces having an angle greater than 90 degrees to said top surface, at least one of said LEDs on at least some of said side surfaces.

9. The lamp of claim 1, wherein said pedestal has a top surface and multiple side surfaces having an angle greater than approximately 105 degrees to said top surface.

10. The bulb of claim 4, wherein said LEDs are arranged with respect to said remote phosphor so that the rays of light emitting in different directions from said LEDs pass through the same thickness of said remote phosphor.

11. The bulb of claim 4, wherein said LEDs approximate a point light source within said remote phosphor.

12. The bulb of claim 2, having an omnidirectional emission pattern with intensity variation of approximately +20 percent or less.

13. The lamp of claim 2, having an omnidirectional emission pattern with intensity variation of approximately +15 percent or less.

26. The lamp of claim 1, wherein said at least one side surface is adjacent said top surface.

27. The lamp of claim 1, wherein a surface adjacent said top surface has an angle equal to or greater than 90 degrees to said top surface.

28. The lamp of claim 1, wherein a surface adjacent said top surface has an angle greater than 90 degrees to said top surface.

29. The lamp of claim 1, wherein the thickness of said elongated pedestal reduces moving down from said top surface.

14. A bulb or lamp light source, comprising:

a plurality of solid state light emitters;

a pedestal having a top surface, a plurality of first side surfaces and a plurality of second side surfaces, wherein said first side surfaces are at an angle greater than 90 degrees to said top surface and said second side surfaces are at an angle less than 90 degrees to said top surface, said solid state light sources on at least some of said first and second side surfaces.

15. The light source of claim 14, wherein said solid state light sources comprise light emitting diodes (LEDs).

16. The light source of claim 14, wherein at least one of said solid state light sources is on said top surface.

17. The light source of claim 14, wherein said pedestal comprises a thermally conductive material.

18. The light source of claim 14, wherein said solid state light sources are electrically coupled in series.

19. The light source of claim 14, wherein said first side surfaces are adjacent said top surface, and said second side surfaces are adjacent said first side surfaces.

20. The light source of claim 19, wherein said solid state light sources are on at least some of said first side surfaces.

21. The light source of claim 19, wherein said solid state light sources are on every other one of said first side surfaces.

22. The light source of claim 14, comprising alternating first and second side surfaces.

23. The light source of claim 14, wherein said first and second side surfaces are adjacent said top surface and are alternating.

24. The light source of claim 23, wherein said solid state light sources are on at least some of said first side surfaces.

25. The light source of claim 14, wherein said top surface is approximately horizontal when said pedestal is vertical.

30. The lamp of claim 14, wherein said first side surfaces are adjacent said top surface.

31. The lamp of claim 14, wherein the thickness of said elongated pedestal reduces moving down from said top surface.