High efficiency LED lamp

• US 9,797,589 B2
• Filed: 07/26/2011
• Issued: 10/24/2017
• Est. Priority Date: 05/09/2011
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Pickard, Paul Kenneth, Negley, Gerald H., Edmond, Mark
• Primary Examiner(s): Williams, Joseph L
• Assistant Examiner(s): RAABE, CHRISTOPHER M
• Application Number:
  US13/190,661
• Publication Number:
  US 20120287601A1
• Time in Patent Office: 2,282 Days
• Field of Search: 36224902
• 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: F21V 29/51 using condensation or evaporation of a fluid, e.g. heat pipes
• CPC Class Codes: F21V 29/58 characterised by the coolants
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/74 with fins or blades
• 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 3/06 characterised by the material
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2105/12 characterised by the geometrical disposition of the light-generating elements, e.g. arranging light-generating elements in differing patterns or densities
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A high-efficiency LED lamp is disclosed. Embodiments of the present invention provide a high-efficiency, high output solid-state lamp. The lamp includes an LED assembly, and an optical element or diffuser disposed to receive light from the LED assembly. The optical element includes a primary exit surface, wherein the primary exit surface is at least about 1.5 inches from the LED assembly. In example embodiments, the optical element is roughly cylindrical in shape, but can take other shapes and be made from various materials. An LED lamp according to some embodiments of the invention has an efficiency of at least about 150 lumens per watt. In some embodiments, the lamp has a light output of at least 1200 lumens. In some embodiments, the LED lamp produces light with a color rendering index (CRI) of at least 90 and a warm white color.

Claims

1. An LED lamp comprising:

an LED assembly including at least first and second LEDs on a mounting surface and being operable to emit light of at least two different colors;

a frustoconical diffuser including a curved surface, and a substantially flat surface having a diameter that is coextensive with the curved surface and at least roughly parallel to the mounting surface, the frustoconical diffuser disposed to receive light from the LED assembly so that a large percentage of the light strikes the curved surface at an oblique angle and exits through the substantially flat surface, at least a portion of the substantially flat surface spaced at least about 1.5 inches from the LED assembly to produce a light output of at least about 1200 lumens with an efficiency of at least about 150 lumens per watt; and

a heatsink structure adjacent to the frustoconical diffuser and the LED assembly with a diameter from 50% to 100% greater than a smallest diameter of the frustoconical diffuser.

2. The LED lamp of claim 1 wherein the light has a warm white color.

3. The LED lamp of claim 2 wherein the light a correlated color temperature of from 2500 to 3500 K.

4. The LED lamp of claim 3 wherein the light a correlated color temperature of from 2800 to 3000 K.

5. The LED lamp of claim 4 wherein the light has a color rendering index of at least 90.

6. The LED lamp of claim 1 wherein the first and second LEDs, when illuminated, emit light having a dominant wavelength from 435 to 490 nm and a dominant wavelength from 600 to 640 nm, respectively, and at least one of the first and second LEDs in packaged with a phosphor, which, when excited, emits light having a dominant wavelength from 540 to 585 nm.

7. The LED lamp of claim 6 wherein the first and second LEDs, when illuminated, emit light having a dominant wavelength from 440 to 480 nm, and a dominant wavelength from 605 to 630 nm, respectively and the phosphor, when excited, emits light having a dominant wavelength from 560 to 580 nm.

8. The LED lamp of claim 1 wherein the portion of the substantially flat surface is spaced at least about 3 inches from the LED assembly.

9. The LED lamp of claim 1 wherein the portion of the substantially flat surface is spaced from about 1.5 to about 8 inches away from the LED assembly.

10. The LED lamp of claim 9 further comprising a power supply electrically connected to the LED assembly.

11. The LED lamp of claim 8 wherein the portion of the substantially flat surface is spaced from about 3 to about 8 inches from the LED assembly.

12. The LED lamp of claim 9 further comprising index matching fluid disposed within the frustoconical diffuser.

13. The LED lamp of claim 9 wherein the frustoconical diffuser comprises deformable material and further comprising at least one support structure connected to the frustoconical diffuser.

14. The LED lamp of claim 9 further comprising a remote wavelength conversion material.

15. The LED lamp of claim 14 wherein the remote wavelength conversion material further comprises phosphor.

16. The LED lamp of claim 14 wherein the remote wavelength conversion material further comprises quantum dots.

17. A method of assembling a high-efficiency LED lamp, the method comprising:

mounting a plurality of LEDs on a mounting surface to provide an LED assembly;

connecting the LED assembly to a line-voltage power supply;

providing a heatsink structure;

installing a frustoconical diffuser with a smallest diameter such that a diameter of the heatsink structure is from 50% to 100% greater than the smallest diameter, wherein the frustoconical diffuser is disposed to receive light from the LED assembly so that a large percentage of the light strikes a curved surface at an oblique angle and exits through a substantially flat surface that has a diameter that is coextensive with the curved surface and that is at least roughly parallel to the mounting surface, and at least a portion of the substantially flat surface is spaced at least about 1.5 inches from the LED assembly and the heatsink structure.

18. The method of claim 17 further comprising connecting an Edison base to the power supply.

19. The method of claim 17 wherein the portion of the substantially flat surface is spaced at least about 3 inches from the LED assembly.

20. The method of claim 17 wherein the mounting of the plurality of LEDs further comprises:

mounting first and second LEDs operable to emit light of at least two different colors; and

packaging one of the first and second LEDs with a phosphor.

21. The method of claim 20 wherein the first and second LEDs, when illuminated, emit light having a dominant wavelength from 435 to 490 nm and a dominant wavelength from 600 to 640 nm, respectively, and the phosphor, when excited, emits light having a dominant wavelength from 540 to 585 nm.

22. The method of claim 21 wherein the first and second LEDs, when illuminated, emit light having a dominant wavelength from 440 to 480 nm, and a dominant wavelength from 605 to 630 nm, respectively and the phosphor, when excited, emits light having a dominant wavelength from 560 to 580 nm.

23. The method of claim 17 wherein the portion of the substantially flat surface is spaced from about 1.5 to about 8 inches away from the LED assembly.

24. The method of claim 23 further comprising installing a support structure for the frustoconical diffuser.

25. A lamp comprising:

an LED assembly to emit light, the LED assembly including a plurality of LEDs on a mounting surface;

a frustoconical diffuser including a curved surface and a substantially flat surface that has a diameter that is coextensive with the curved surface and is at least roughly parallel to the mounting surface so that a large percentage of the light strikes the curved surface at an oblique angle and exits through the substantially flat surface, wherein at least a portion of the substantially flat surface is spaced at least about 1.5 inches from the LED assembly; and

a heatsink structure adjacent to the frustoconical diffuser and the LED assembly with a diameter from 50% to 100% greater than a smallest diameter of the frustoconical diffuser.

26. The lamp of claim 25 wherein the light emitted has a color rendering index of at least 90 and a coordinated color temperature CCT of 2500 to 3500 K.

27. The lamp of claim 26 wherein the light emitted has a CCT of 2800 to 3000.

28. The lamp of claim 25 wherein the portion of the substantially flat surface is at least 3 inches from the LED assembly.

29. The lamp of claim 25 wherein the portion of the substantially flat surface is less than 8 inches from the LED assembly.

30. The lamp of claim 28 wherein the portion of the substantially flat surface is less than 8 inches from the LED assembly.

31. The LED lamp of claim 26 further comprising index matching fluid disposed within the frustoconical diffuser.

32. The LED lamp of claim 26 wherein the frustoconical diffuser comprises deformable material and further comprising at least one support structure connected to the frustoconical diffuser.

33. The LED lamp of claim 26 further comprising a remote wavelength conversion material.

34. The LED lamp of claim 33 wherein the remote wavelength conversion material further comprises quantum dots.

35. The LED lamp of claim 33 wherein the remote wavelength conversion material further comprises phosphor.