Multi-element LED lamp

• US 8,847,242 B2
• Filed: 12/20/2013
• Issued: 09/30/2014
• Est. Priority Date: 05/03/2006
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Hutchins, Edward Lloyd
• Primary Examiner(s): Sefer, A.
• Application Number:
  US14/136,846
• Publication Number:
  US 20140104865A1
• Time in Patent Office: 284 Days
• Field of Search: 257/79, 257/89, 257/94, 257/96, 257/98
• US Class Current: 257/79
• CPC Class Codes: F21S 41/143 the main emission direction of the LED being parallel to the optical axis of the illuminating device
• CPC Class Codes: F21S 41/147 the main emission direction of the LED being angled to the optical axis of the illuminating device
• CPC Class Codes: F21S 41/321 the reflector being a surface of revolution or a planar surface, e.g. truncated
• CPC Class Codes: F21S 41/337 the reflector having a structured surface, e.g. with facets or corrugations
• CPC Class Codes: F21S 41/60 characterised by a variable light distribution
• CPC Class Codes: F21S 41/663 by switching light sources by switching incandescent light sources F21S41/162
• CPC Class Codes: F21V 7/04 Optical design
• 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 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/00014 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 33/54 having a particular shape
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A light emitting diode device (e.g., LED package) may include at least two light emitting devices that can be switched independently of one another and thus may be useful in vehicular lighting applications, for example low and high beam headlights. A LED device may include a first LED die and at least one additional LED die disposed at different positions within a common reflector cup or relative to a common lens. Multiple LED sub-assemblies may be mounted to a common lead frame along non-coincident principal axes. Methods for varying intensity or color from multi-LED lamps are further provided.

Claims

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

a reflector cup comprising a vertex, a focal point, and an inside surface;

an array of LEDs disposed within the reflector cup and mounted on or over a common submount, wherein emissions of at least some LEDs of the array of LEDs are arranged to be reflected by an inside surface of the reflector cup, wherein a center of the array of LEDs is offset relative to the vertex of the reflector cup; and

a lens arranged to transmit at least a portion of light generated by the LEDs and reflected by the reflector cup;

wherein the LED lamp comprises at least one of the following features (a) and (b);

(a) the reflector cup is asymmetric; and

(b) the lens is asymmetric.

2. The LED lamp of claim 1, wherein the reflector cup is asymmetric.

3. The LED lamp of claim 1, wherein the lens is asymmetric.

4. The LED lamp of claim 1, wherein the reflector cup is asymmetric and the lens is asymmetric.

5. The LED lamp of claim 1, wherein at least a portion of the common submount is substantially planar, and wherein at least a basal portion of each LED of the array of LEDs is arranged on a substantially planar portion of the common substrate.

6. The LED lamp of claim 1, wherein the submount comprises a lead frame.

7. The LED lamp of claim 1, wherein the submount comprises a printed circuit board.

8. The LED lamp of claim 1, wherein the reflector cup is mounted on or over the submount.

9. The LED lamp of claim 1, wherein the reflector cup is asymmetric, and at least a portion of the reflector cup is faceted.

10. The LED lamp of claim 1, wherein at least a portion of the reflector cup comprises a geometric shape selected from the group consisting of parabolic, ellipsoid, and compound curves.

11. The LED lamp of claim 1, wherein each LED of the array of LEDs comprises a surface mount LED.

12. The LED lamp of claim 1, wherein the lens is arranged to contact the reflector cup.

13. The LED lamp of claim 1, further comprising a common heat spreader arranged between the array of LEDs and the common submount.

14. The LED lamp of claim 1, further comprising at least one phosphor material layer arranged between the array of LEDs and the lens, wherein the at least one phosphor material is remotely located relative to each LED of the array of LEDs.

15. The LED lamp of claim 1, wherein each LED of the array of LEDs is arranged non-coincident with the vertex of the LED lamp.

16. The LED lamp of claim 1, wherein at least two LEDs of the array of LEDs are independently controllable relative to one another.

17. The LED lamp of claim 1, wherein each LED of the array of LEDs is arranged to output white light.

18. The LED lamp of claim 1, wherein the array of LEDs comprises at least one LED arranged to output red light or infrared light.

19. The LED lamp of claim 1, comprising a photosensor, wherein operation of the LED lamp is controlled responsive to an output of the photosensor.

20. The LED lamp of claim 1, comprising a plurality of LED packages.

21. A vehicular headlamp comprising the LED lamp of claim 1.

22. A recessed lighting apparatus comprising the LED lamp of claim 1.

23. A method for illuminating a surface or roadway utilizing a LED lamp according to claim 1, the method comprising supplying electric power to the array of LEDs.