SINGLE CHIP LED AS COMPACT COLOR VARIABLE LIGHT SOURCE

• US 20100109575A1
• Filed: 11/28/2005
• Published: 05/06/2010
• Est. Priority Date: 12/06/2004
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Hoelen, Christoph Gergard August, Ansems, Johannes Petrus Maria
• Granted Patent: US 8,026,532 B2
• Time in Patent Office: Days
• US Class Current: 315/312
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials

Abstract

The present invention relates to a color variable light-emitting device comprising an array of a plurality of LEDs formed on one highly resistive substrate, which array comprises a first, a second and a third set of at least one LED arranged to provide light of a first, a second and a third color, respectively. At least one of the sets is independently addressable. Further, each light-emitting diode in the array has a separate connection to a circuitry, and at least one of the sets comprises at least two LEDs, interconnected in series via the circuitry. Thus, all connections between separate LEDs, for example in the same set, can be done via the circuitry. This also allows for a very dense packing of the LEDs in the array, as no interconnects between different LEDs of the array need to be arranged in the array.

Claims

1. A color variable light-emitting device, comprising:

an array (1) of a plurality of light-emitting diodes (2, 3, 4) formed on one highly resistive substrate (10), said array comprising at least a first set of at least one light-emitting diode (2) arranged to provide light of a first color, a second set of at least one light-emitting diode (3) arranged to provide light of a second color and a third set of at least one light-emitting diode (4) arranged to provide light of a third color; and

a sub-mount (5) on which said array (1) is arranged, said sub-mount being provided with a circuitry (21, 22, 23), to which said array of light-emitting diodes is connected, characterized in that each light-emitting diode in said array has a separate connection to said circuitry;

at least one of said sets comprises at least two light-emitting diodes, interconnected in series via said circuitry; and

said circuitry comprises external connectors (7, 17, 8, 18, 9, 19) to independently address at least one of said at least first, second and third sets.

2. A device according to claim 1, wherein said circuitry comprises a first part (22) and a second part (23), said first part being connected to said independently addressable set of light-emitting diodes, and being electrically isolated from said second part.

3. A device according to claim 1, wherein said sub-mount is a multilayer sub-mount and said circuitry (21, 22, 23) is arranged partly on a first layer (31) of the sub-mount and partly on a second layer (32) of the sub-mount.

4. A device according to claim 2, wherein said first part (22) of said circuitry is arranged on a first layer (31) of the sub-mount and said second part (23) of said circuitry is arranged on a second layer (32) of the sub-mount.

5. A device according to claim 1, wherein the light-emitting diode(s) of said first set is provided with a first wavelength-converting compound arranged to convert light emitted by said diode(s) into light of said first provided color, and the light-emitting diode(s) of said second set is provided with a second wavelength-converting compound arranged to convert light emitted by said diode(s) into light of said second provided color

6. A device according to claim 5, wherein the light emitted by said light-emitting diodes is blue light, and wherein said first provided color is green and said second provided color is red.

7. A device according to claim 1, wherein the light-emitting diode(s) of said third set is provided with a third wavelength-converting compound arranged to convert light emitted by said diode(s) into light of said third provided color.

8. A device according to claim 7, wherein the light emitted by said light-emitting diodes is UV-light, and wherein said first provided color is green, said second provided color is red, and said third provided color is blue.

9. An array according to claim 5, wherein said wavelength-converting compound is deposited on said light-emitting diode(s).

10. An array according to claim 5, wherein said wavelength-converting compound is arranged in an area of a layer which is arranged on said array, said area covering at least part of said light-emitting diode(s).