Light unit having light emitting diodes

• US 6,860,620 B2
• Filed: 05/09/2003
• Issued: 03/01/2005
• Est. Priority Date: 05/09/2003
• Status: Expired due to Term

• Current Assignee: Document Security Systems, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Kuan, Yew Cheong, Lim, Seong Choon, Foong, Kar Phooi, Ou, Wen Ya
• Primary Examiner(s): Cariaso, Alan
• Assistant Examiner(s): Tsidulko, Mark
• Application Number:
  US10/434,818
• Publication Number:
  US 20040223327A1
• Time in Patent Office: 662 Days
• Field of Search: 362/294, 362/373, 361/760, 361/761, 361/764, 361/767, 361/768, 361/684, 361/686, 361/720, 361/777, 174/252, 174/250
• US Class Current: 362/294
• CPC Class Codes: B60Q 1/2607 comprising at least two indicating lamps
• CPC Class Codes: B60Q 1/2696 Mounting of devices using LEDs
• CPC Class Codes: F21S 4/22 flexible or deformable, e.g. into a curved shape
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 43/15 Strips of light sources
• CPC Class Codes: F21S 45/47 Passive cooling, e.g. using fins, thermal conductive elements or openings
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/89 Metals
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05K 1/0209 External configuration of printed circuit board adapted for heat dissipation, e.g. lay-out of conductors, coatings
• CPC Class Codes: H05K 1/189 characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence
• CPC Class Codes: H05K 2201/09781 Dummy conductors, i.e. not used for normal transport of current; Dummy electrodes of components
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence

Abstract

A light unit is provided that includes a thin flexible substrate layer. A number of flexible electrical tracks are formed on the flexible substrate layer. A number of Light Emitting Diodes (LEDs) are arranged on the flexible substrate layer along the electrical tracks and are electrically connected to the electrical tracks such that the light unit is both thin and flexible.

Claims

1. A light unit comprising:

a thin and flexible substrate layer;

a plurality of flexible tracks, including at least a heat sink track, formed on the flexible substrate, wherein the flexible tracks further comprise an anode track and a cathode track, and wherein the heat sink track is formed between the anode and cathode tracks;

a plurality of Light Emitting Diodes (LEDs) arranged on the flexible substrate layer along the flexible tracks and being electrically connected to some of the flexible tracks such that the light unit is both thin and flexible.

2. The light unit of claim 1, wherein the flexible substrate layer comprises an electrically insulating material and is about 25.4 micrometer in thickness.

3. Light unit of claim 1, wherein the flexible tracks are multi-layer tracks that comprise a copper layer on the substrate layer, a nickel layer arranged over the copper layer, and a gold layer over the nickel layer.

4. The light unit of claim 3, wherein the copper layer is about 17.78 micro-meter thick, the nickel layer is between 2.54 to 7.62 micro-meter in thickness and the gold layer is at least 0.76 micrometer in thickness.

5. The light unit of claim 1, wherein each of the LEDs is arranged on the substrate layer along the flexible tracks using a surface mount technology.

6. A light unit comprising:

a thin and flexible substrate layer;

a plurality of flexible tracks, including at least a heat sink track, formed on the flexible substrate;

a plurality of Light Emitting Diodes (LEDs) arranged on the flexible substrate layer along the flexible tracks and being electrically connected to some of the flexible tracks such that the light unit is both thin and flexible;

a heat-conducting frame surrounding the substrate layer, the heat sink track being thermally connected to the frame.

7. The light unit of claim 6, further comprising a heat conducting metal plate attached with the substrate layer via an adhesive paste and in contact with the heat-conducting frame.

8. The light unit of claim 6, wherein the flexible substrate layer comprises an electrically insulating material and is about 25.4 micrometer in thickness.

9. A motor vehicle lamp comprising:

a light unit that further comprises

a thin flexible substrate layer;

a plurality of flexible tracks, including at least a heat sink track, formed on the flexible substrate, wherein the flexible tracks further comprise an anode track and a cathode track, and wherein the heat sink track is formed between the anode and cathode tracks;

a plurality of Light Emitting Diodes (LEDs) arranged on the substrate layer along the flexible tracks and being electrically connected to some of the flexible tracks such that the light unit is both thin and flexible.

10. The motor vehicle lamp of claim 9, wherein the flexible substrate layer comprises an electrically insulating material and is about 25.4 micrometer in thickness.

11. The motor vehicle lamp of claim 9, wherein the flexible tracks are multi-layer tracks that comprise a copper layer on the substrate layer, a nickel layer arranged over the copper layer, and a gold layer over the nickel layer.

12. The motor vehicle lamp of claim 11, wherein the copper layer is approximately 17.78 micrometer thick, the nickel layer is between 2.54 to 7.62 micrometer in thickness and the gold layer is at least 0.76 micro-meter in thickness.

13. The motor vehicle lamp of claim 9, wherein the lamp is a tail lamp.

14. The motor vehicle lamp of claim 9, further comprising a casing within which the light unit is arranged with the transparent part being provided as a cover covering the casing.

15. The motor vehicle lamp of claim 9, wherein the light unit further comprises an optical lens arranged on the LEDs for controlling light emitted thereby, wherein each of the LEDs is arranged on the substrate layer along the flexible tracks using a surface mount technology.

16. A motor vehicle lamp comprising:

a light unit that further comprises

a thin flexible substrate layer;

a plurality of flexible tracks, including at least a heat sink track, formed on the flexible substrate;

a plurality of Light Emitting Diodes (LEDs) arranged on the substrate layer along the flexible tracks and being electrically connected to some of the flexible tracks such that the light unit is both thin and flexible; and

a heat-conducting frame surrounding the substrate layer, the heat sink track being thermally connected to the frame.

17. The motor vehicle lamp of claim 16, wherein the light unit further comprises a heat conducting metal plate attached with the substrate layer via an adhesive paste and in contact with the heat-conducting frame.

18. The motor vehicle lamp of claim 16, wherein the flexible substrate layer comprises an electrically insulating material and is about 25.4 micrometer in thickness.

19. The motor vehicle lamp of claim 16, wherein the lamp is a tail lamp.

20. The motor vehicle lamp of claim 16, further comprising a casing within which the light unit is arranged with the transparent part being provided as a cover covering the casing.

21. The motor vehicle lamp of claim 16, wherein the light unit further comprises an optical lens arranged on the LEDs for controlling light emitted thereby, wherein each of the LEDs is arranged on the substrate layer along the flexible tracks using a surface mount technology.