Efficient LED array

• US 8,371,718 B2
• Filed: 02/12/2010
• Issued: 02/12/2013
• Est. Priority Date: 09/29/2008
• Status: Active Grant

• Current Assignee: BX LED LLC (Ni, Wang & Massand, PLLC)
• Original Assignee: Bridgelux Incorporated
• Inventors: Helbing, Rene Peter
• Primary Examiner(s): Husar, Stephen F
• Assistant Examiner(s): CRANSON JR, JAMES W
• Application Number:
  US12/705,240
• Publication Number:
  US 20100142196A1
• Time in Patent Office: 1,096 Days
• Field of Search: 362/218, 362/294, 362/249.02, 257/88, 257/98
• US Class Current: 362/294
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21L 4/027 the light sources being a LED
• CPC Class Codes: F21S 6/00 Lighting devices intended to be free-standing F21S9/00, F21S10/00, F21S13/12 take precedence lighting devices specially adapted to be transported from place to place, e.g. lighting devices carried on wheeled supports F21L; details of supports for lighting devices F21V21/00
• CPC Class Codes: F21S 8/08 with a standard F21S6/00 takes precedence
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21W 2131/103 of streets or roads
• 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]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• 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 33/60 Reflective elements
• CPC Class Codes: H01L 33/64 Heat extraction or cooling elements

Abstract

An efficient LED array. In an aspect, an LED apparatus includes a metal substrate having a reflective surface, and LED chips mounted directly to the reflective surface to allow for thermal dissipation, and wherein at least a portion of the LED chips are spaced apart from each other to allow light to reflect from a portion of the reflective surface that is located between the portion of the LED chips. In another aspect, a method includes configuring a metal substrate to have a reflective surface, and mounting a plurality of LED chips directly to the reflective surface of the metal substrate to allow for thermal dissipation, and wherein at least a portion of the LED chips are spaced apart from each other to allow light to reflect from a portion of the reflective surface that is located between the portion of the LED chips.

Claims

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

a heat sink;

a metal substrate having a reflective surface, the metal substrate is mounted directly to the heat sink without a dielectric insulator in between;

a dielectric insulating layer disposed on a portion of the metal substrate;

a plurality of LED chips mounted directly to the reflective surface of the metal substrate without a dielectric insulator in between to allow for thermal dissipation, and wherein at least a portion of the LED chips are spaced apart from each other to allow light from the portion of the LED chips to reflect from a portion of the reflective surface that is located between the portion of the LED chips; and

a bonding pad disposed on the dielectric insulating layer, the bonding pad is electrically connected to at least one of the plurality of LED chips.

2. The lamp of claim 1, wherein the reflective surface comprises polished aluminum.

3. The lamp of claim 1, wherein the reflective surface comprises silver plating.

4. The lamp of claim 1, wherein the reflective surface has a reflectivity of 70% or greater.

5. The lamp of claim 1, wherein the at least a portion of the LED chips form an array having a chip spacing that is approximately 0.5 millimeters or greater.

6. The lamp of claim 1, wherein the plurality of LED chips provide separate thermal and electrical paths.

7. The lamp of claim 1, wherein the plurality of LED chips have a first surface that is mounted to the reflective surface, and electrical contacts that are provided on one or more surfaces that are not the first surface.

8. The lamp of claim 1, wherein the metal substrate is mounted directly to a heat sink.

17. The LED lamp of claim 1 further comprising a package;

wherein the package comprises a power supply that is electrically coupled to the bonding pad.

9. An illumination device comprising:

a power source;

a light emitting diode lamp in electrical communication with the power source, the light emitting diode lamp comprising;

a package; and

a light emitting diode apparatus coupled to the package and comprising;

a heat sink;

a metal substrate having a reflective surface, the metal substrate is mounted directly to the heat sink without a dielectric insulator in between;

a dielectric insulating layer disposed on a portion of the metal substrate;

a plurality of LED chips mounted directly to the reflective surface of the metal substrate without a dielectric insulator in between to allow for thermal dissipation, and wherein at least a portion of the LED chips are spaced apart from each other to allow light from the portion of the LED chips to reflect from a portion of the reflective surface that is located between the portion of the LED chips;

a bonding pad disposed on the dielectric insulating layer, the bonding pad is electrically connected to at least one of the plurality of LED chips and is electrically coupled to the power source.

10. The illumination device of claim 9, wherein the reflective surface comprises polished aluminum.

11. The illumination device of claim 9, wherein the reflective surface comprises silver plating.

12. The illumination device of claim 9, wherein the reflective surface has a reflectivity of 70% or greater.

13. The illumination device of claim 9, wherein the at least a portion of the LED chips form an array having a chip spacing that is approximately 0.5 millimeters or greater.

14. The illumination device of claim 9, wherein the plurality of LED chips provide separate thermal and electrical paths.

15. The illumination device of claim 9, wherein the plurality of LED chips have a first surface that is mounted to the reflective surface, and electrical contacts that are provided on one or more surfaces that are not the first surface.

16. The illumination device of claim 9, wherein the metal substrate is mounted directly to a heat sink.