Light emission device and method utilizing multiple emitters

• US 8,120,240 B2
• Filed: 04/07/2009
• Issued: 02/21/2012
• Est. Priority Date: 01/10/2005
• Status: Active Grant

• Current Assignee: Cree Incorporated
• Sponsoring Entity: Cree Incorporated
• Inventors: Brandes, George R.
• Primary Examiner(s): Guharay, Karabi
• APPLICATION: US 20090195137A1
• Time in USPTO: 1050 Days
• Field of Search: 313/498, 313501-503, 313/498.501, 362/800
• US Class Current: 313/501
• CPC Class Codes: C09K 11/586 : with alkaline earth metals
• CPC Class Codes: C09K 11/623 : with zinc or cadmium
• CPC Class Codes: C09K 11/7421 : with alkaline earth metals
• CPC Class Codes: C09K 11/7702 : with zinc or cadmium
• CPC Class Codes: C09K 11/7721 : Aluminates; Silicates
• CPC Class Codes: C09K 11/7734 : Aluminates; Silicates
• 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: F21Y 2113/17 : forming a single encapsulated light source
• CPC Class Codes: F21Y 2115/10 : Light-emitting diodes [LED]
• 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 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y02B 20/181 : Fluorescent powders
• CPC Class Codes: Y10S 362/80 : Light emitting diode

Abstract

A light emission device includes multiple electrically activated solid state emitters (e.g., LEDs) having differing spectral output from one another; and/or phosphor material including one or more phosphors arranged to receive spectral output from at least one of the solid state emitters and to responsively emit a phosphor output, to provide spectral output. In one arrangement, at least four electrically activated solid state emitters each have different spectral outputs in the visible range, with the emitters arranged in an array positioned on a single reflector cup or other support, with at least two solid state emitters differing substantially in size. Aggregated output may include white light having a color temperature in any of several desired ranges.

Claims

1. A light emission device comprising at least four electrically activated solid state emitters each having different spectral outputs in the visible range, and adapted to emit an aggregated spectral output having at least four different color peaks in the visible range, wherein the at least four solid state emitters are arranged in an array with each solid state emitter being positioned on a single reflector cup or other support structure, and wherein at least two solid state emitters of the at least four solid state emitters differ substantially in top area.

2. The light emission device of claim 1, wherein the at least four electrically activated solid state emitters comprises a first, a second, a third, and a fourth solid state emitter, and the light emission device further comprises at least one phosphor material arranged to interact with at least one of the first, second, third, and fourth solid state emitter to responsively emit a fifth spectral output including emission in the visible range.

3. The light emission device of claim 2, wherein the at least one phosphor material absorbs only a portion of the output of any solid state emitter of the at least four solid state emitters.

4. The light emission device of claim 2, wherein the at least four electrically activated solid state emitters comprises a first, a second, a third, and a fourth solid state emitter, and wherein the at least one phosphor material is conformally coated over any of the first, second, third, and fourth solid state emitter.

5. The light emission device of claim 2, wherein the at least one phosphor material is disposed over each of the first, second, third, and fourth solid state emitter.

6. The light emission device of claim 2, wherein the at least one phosphor material comprises a plurality of phosphor materials.

7. The light emission device of claim 1, including a covering material comprising at least one of a glass composition and a polymeric composition, wherein said covering material is disposed over each solid state emitter of the at least four solid state emitters.

8. The light emission device of claim 1, adapted to provide an aggregated spectral output of white light.

9. The light emission device of claim 1, adapted to provide white light output having a color temperature in one of the following white light color temperature regimes (A), (B) and (C):

(A) white light having a color temperature in a range of from 1350°

K to 1550°

K;

(B) white light having a color temperature in a range of from 2400°

K to 3550°

K; and

(C) white light having a color temperature in a range of from 4950°

K to 6050°

K.

10. The light emission device of claim 1, wherein current is sourced individually to each solid state emitter of the at least four solid state emitters.

11. The light emission device of claim 1, wherein the at least four solid state emitters comprise at least four LEDs.

12. The light emission device of claim 11, wherein the at least four LEDs are selected from the group consisting of blue LEDs, aqua LEDs, green LEDs, yellow LEDs, and red LEDs.

13. A method of generating light, the method comprising supplying current to at least four electrically activated solid state emitters each having different spectral outputs in the visible range, and adapted to emit an aggregated spectral output having at least four different color peaks in the visible range, wherein the at least four solid state emitters are arranged in an array with each solid state emitter being positioned on a single reflector cup or other support structure, and wherein at least two solid state emitters of the at least four solid state emitters differ substantially in top area.

14. The method of claim 13, wherein current is sourced individually to each solid state emitter of the at least four solid state emitters.