LED Based Lamp

• US 20100237760A1
• Filed: 03/10/2010
• Published: 09/23/2010
• Est. Priority Date: 03/17/2009
• Status: Active Grant

• Current Assignee: Intematix Corporation
• Original Assignee: Intematix Corporation
• Inventors: Yang, Haitao
• Granted Patent: US 8,541,931 B2
• Time in Patent Office: Days
• US Class Current: 313/46
• 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: F21S 8/02 of recess-mounted type, e.g. downlighters specially adapted for vehicle exteriors F21S41/00-F21S45/00
• CPC Class Codes: F21S 8/026 intended to be recessed in a ceiling or like overhead structure, e.g. suspended ceiling
• CPC Class Codes: F21V 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 15/01 Housings, e.g. material or assembling of housing parts F21V15/02 takes precedence housings forming signs or letters G09F13/04
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/78 with helically or spirally arranged fins or blades
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 29/86 Ceramics or glass
• CPC Class Codes: F21V 29/87 Organic material, e.g. filled polymer composites; Thermo-conductive additives or coatings therefor
• CPC Class Codes: F21V 29/89 Metals
• CPC Class Codes: F21V 7/04 Optical design
• CPC Class Codes: F21V 7/24 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 2115/10 Light-emitting diodes [LED]

Abstract

A lamp comprises: a thermally conductive body; a plurality of LEDs configured as an array and mounted in thermal communication with the body and a light reflective hood located in front of the plane of light emitting diodes. The hood has at least two frustoconical light reflective surfaces that surround the array of LEDs and are configured such that in operation light emitted by the lamp is within a selected emission angle (beam spread). The hood is configured such that in operation a variation in illuminance (luminous flux per unit area incident on a surface) is 10% or less over approximately a third to one half of the selected emission angle.

Claims

1. A lamp comprising:

a thermally conductive body;

a plurality of light emitting diodes configured as an array and mounted in thermal communication with the body; and

a light reflective hood located in front of the plane of light emitting diodes, wherein the hood has at least two frustoconical light reflective surfaces that surround the array of light emitting diodes and are configured such that in operation light emitted by the lamp is within a selected emission angle.

2. The lamp according to claim 1, wherein the at least two light reflective surfaces are contiguous.

3. The lamp according to claim 1, wherein the hood is configured such that in operation a variation in illuminance is 10% or less over approximately a third of the selected emission angle.

4. The lamp according to claim 1, wherein the hood is configured such that in operation a variation in illuminance is 10% or less over approximately half of the selected emission angle.

5. The lamp according to claim 1, wherein the hood is configured such that in operation a proportion of total light emission emitted within the selected emission angle is selected from the group consisting of:

at least 90%, at least 95% and at least 98%.

6. The lamp according to claim 1, and further comprising a light diffuser interposed between the array of light emitting diodes and the hood.

7. The lamp according to claim 1, wherein the hood is generally cylindrical in form.

8. The lamp according to claim 1, wherein the hood comprises a thermally conductive material.

9. The lamp according to claim 8, wherein the hood has a thermal conductivity selected from the group consisting of at least 150 Wm⁻

1K<sup>−

1</sup> and at least 200 Wm<sup>−

1</sup>K<sup>−

1</sup>.

10. The lamp according to claim 8, wherein the hood is in thermal communication with the thermally conductive body.

11. The lamp according to claim 1, wherein the hood comprises a material selected from the group consisting of:

aluminum, an alloy of aluminum, a magnesium alloy, a plastics material, a metal loaded plastics material and a thermally conductive ceramic material.

12. The lamp according to claim 1, and further comprising a light reflective material applied to the at least two light reflective surfaces.

13. The lamp according to claim 1, wherein the selected emission angle is in a range 8°

to 60°

.

14. The lamp according to claim 13, wherein the selected emission angle is selected from the group consisting of being of order:

20°

, 30°

, 45° and

60°

.

15. The lamp according to claim 1, wherein the body is configured such that the lamp can be fitted in an existing lighting fixture.

16. The lamp according to claim 1, wherein the form of the body is selected from the group consisting of being:

generally cylindrical, generally conical and generally hemispherical in form.

17. The lamp according to claim 1, wherein the body is configured such that it has a form factor that resembles a standard form selected from the group consisting of:

PAR38, PAR20, PAR30, PAR36, PAR56, PAR64, MR16 and MR11.

18. The lamp according to claim 1, wherein the body comprises a material selected from the group consisting of:

aluminum, an alloy of aluminum, a magnesium alloy, a plastics material, a metal loaded plastics material, a thermally conductive ceramic material and aluminum silicon carbide.

21. The lamp according to claim 1, wherein the hood is configured such that a variation in illuminance is 10% or less over approximately half of the selected emission angle.

19. A lamp comprising:

a thermally conductive body;

a plurality of light emitting diodes configured as an array and mounted in thermal communication with the body;

a light diffuser overlying the array of light emitting diodes; and

a light reflective hood overlying the light diffuser, wherein the hood is configured to surround the array of light emitting diodes such that in operation light emitted by the lamp is within a selected emission angle.

20. The lamp according to claim 19, wherein the hood is configured such that a variation in illuminance is 10% or less over approximately a third of the selected emission angle.

22. The lamp according to claim 19, wherein the hood is configured such that in operation a proportion of total light emission emitted within the selected emission angle is selected from the group consisting of:

at least 90%, at least 95% and at least 98%.

23. The lamp according to claim 19, wherein the hood comprises at least two frustoconical light reflective surfaces that surround the array of light emitting diodes.

24. The lamp according to claim 23, wherein the light reflective surfaces are contiguous.

25. The lamp according to claim 19, wherein the emission angle is in a range 8°

to 60°

.