APPARATUS INCORPORATING AN OPTICALLY TRANSMITTING CIRCUIT BOARD

• US 20130026922A1
• Filed: 07/29/2011
• Published: 01/31/2013
• Est. Priority Date: 07/29/2011
• Status: Abandoned Application

• Current Assignee: OSRAM Sylvania Inc. (Ams-Osram AG)
• Original Assignee: OSRAM Sylvania Inc. (Ams-Osram AG)
• Inventors: Allen, Steven C., Ghiu, Camil
• Application Number:
  US13/194,537
• Publication Number:
  US 20130026922A1
• Time in Patent Office: Days
• US Class Current: 315/113
• CPC Class Codes: F21K 9/233 specially adapted for generating a spot light distribution, e.g. for substitution of reflector lamps
• CPC Class Codes: F21V 29/506 of globes, bowls or cover glasses
• CPC Class Codes: F21V 29/773 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 7/0008 providing for indirect lighting
• CPC Class Codes: F21Y 2109/00 Light sources with light-generating elements disposed on transparent or translucent supports or substrates
• CPC Class Codes: H05K 1/0306 Inorganic insulating substrates, e.g. ceramic, glass
• CPC Class Codes: H05K 2201/0108 Transparent
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]

Abstract

An apparatus and method of a lamp including an optically transmitting, thermally conductive substrate is provided. The substrate has a first side, a second side, and at least one edge. At least one solid state light source, such as but not limited to a light emitting diode, is disposed on the first side of the substrate. The at least one solid state light source (e.g., light emitting diode) includes at least one junction having a first junction temperature. The substrate used is an optically transmitting, thermally conductive substrate, with a thermal conductivity greater than or equal to about 3 W/mK.

Claims

1. An apparatus comprising:

a substrate having a first side, a second side, and at least one edge; and

at least one light emitting diode (LED) disposed on the first side, the at least one LED comprising at least one junction having a first junction temperature;

wherein the substrate is an optically transmitting, thermally conductive substrate and the substrate has a thermal conductivity greater than or equal to about 3 W/mK.

2. The apparatus of claim 1, wherein the substrate is configured such that the temperature drop between the at least one junction and the at least one edge is less than or equal to about 40°

C.

3. The apparatus of claim 1, wherein the substrate has a thickness ranging from about 0.1 mm to about 6 mm.

4. The apparatus of claim 3, wherein the substrate comprises at least one material selected from the group consisting of AlN, polycrystalline Al₂O₃, BaF₂, BeO, CaF₂, InGaN, LiF, LiNbO₃, LiTaO₃, NaF, MgF₂, MgO, quartz, sapphire, SiC, Y₂O₃, Y₃Al₅O₁₂, and ZrO₂.

5. The apparatus of claim 1, wherein the substrate has a thermal conductivity ranging from about 3.5 to about 400 W/mK.

6. The apparatus of claim 1, wherein the first junction temperature is less than or equal to about 125°

C.

7. The apparatus of claim 1, further comprising an optic, wherein the first side of the substrate faces the optic.

8. The apparatus of claim 7, wherein the optic comprises an aperture, and the substrate and the at least one LED are disposed at or within the aperture.

9. The apparatus of claim 7, wherein the optic comprises a reflector.

10. The apparatus of claim 1, further comprising a heat sink, the heat sink comprising a base, an opening positioned substantially opposite to the base, and a cavity therebetween, wherein the substrate is disposed within the cavity or across the opening such that the first side of the substrate faces the base.

11. The apparatus of claim 10, wherein the substrate conducts heat from the at least one junction to the heat sink, and is configured such that the temperature drop between the at least one junction and the heat sink is less than or equal to about 40°

C.

12. An apparatus, comprising:

a heat sink having a base, an opening, and a cavity therebetween;

an optically transmitting, thermally conductive substrate supported within the cavity or across the opening, the substrate comprising a first side, a second side, and at least one edge, the first side facing the base;

at least one light emitting diode (LED) disposed on the first side of the substrate, the at least one LED comprising at least one junction having a first junction temperature;

wherein the substrate has a thermal conductivity greater than or equal to about 3 W/mK.

13. The apparatus of claim 12, further comprising an optic positioned within the cavity and between the at least one LED and the base.

14. The apparatus of claim 13, wherein the at least one LED emits rays, and at least a portion of the rays are reflected by the optic through the substrate.

15. The apparatus of claim 12, wherein said substrate is configured to conduct heat produced by the at least one LED to the heat sink, the substrate being configured such that the temperature drop between said at least one junction and said heat sink is less than or equal to about 40°

C.

16. The apparatus of claim 12, wherein the first junction temperature is less than or equal to about 125°

C.

17. The apparatus of claim 12, wherein the substrate has a thermal conductivity ranging from about 3.5 to about 400 W/mK.

18. A method, comprising:

providing a lamp, the lamp comprising;

an optically transmitting, thermally conductive substrate comprising a first side, a second side, and at least one edge; and

at least one light emitting diode (LED) disposed on the first side, the at least one LED comprising at least one junction having a first junction temperature;

emitting heat and radiation within a waveband from the at least one LED;

causing at least a portion of the radiation within the waveband to pass through the substrate; and

conducting, via the substrate, the heat emitted by the at least one LED from the junction to the at least one edge;

wherein the substrate has a thermal conductivity greater than or equal to about 3 W/mK.

19. The method of claim 18, wherein the lamp further comprises an optic, and wherein the method further comprises reflecting at least a portion of the radiation emitted by the at least one LED off a surface of the optic and through the substrate.

20. The method of claim 18, wherein a temperature drop from the junction to the at least one edge is less than or equal to about 40°

C.