Automotive lighting device

• US 20040037087A1
• Filed: 08/21/2002
• Published: 02/26/2004
• Est. Priority Date: 08/21/2002
• Status: Active Grant

• Current Assignee: North American Lighting Incorporated (Koito Manufacturing Company Limited)
• Original Assignee: North American Lighting Incorporated (Koito Manufacturing Company Limited)
• Inventors: Desai, Deval M.
• Granted Patent: US 6,773,154 B2
• Time in Patent Office: Days
• US Class Current: 362/541
• CPC Class Codes: B60Q 1/26 the devices being primarily intended to indicate the vehicle, or parts thereof, or to give signals, to other traffic
• 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: F21S 41/24 Light guides
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 43/235 Light guides
• CPC Class Codes: F21S 45/47 Passive cooling, e.g. using fins, thermal conductive elements or openings
• CPC Class Codes: F21S 45/48 with means for conducting heat from the inside to the outside of the lighting devices, e.g. with fins on the outer surface of the lighting device
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 29/85 characterised by the material liquid coolants F21V29/56
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

An exterior automotive lighting device is provided. The device includes a light guide housing and a single Light Emitting Semiconductor Device (LESD). The light guide housing includes reflective material and optical elements to reflect emitted photons from the single LESD in multiple directions. The light guide has a thermally conductive material and thermally conductive connectors to dissipate heat generated by the single LESD. The lighting device may be used in accordance with lighting systems, such as a high mount stop lamp and a tail lamp on an automobile.

Claims

1. A lighting device comprising:

a light guide having a first and a second surface;

a light source comprising a single Light Emitting Semiconductor Device (LESD), the single LESD coupled to the light guide to radiate light through the first surface;

a control circuit arranged between the first and the second surface of the light guide, the control circuit electrically coupled to the single LESD to control operation of the single LESD; and

a heat collector coupled to the light guide, the heat collector operable to dissipate heat generated by the single LESD and the control circuit.

2. The lighting device of claim 1, wherein the single LESD is a Light Emitting Diode (LED).

3. The lighting device of claim 1, wherein the single LESD is coupled to the light guide using a thermally conductive connector.

4. The lighting device of claim 3, wherein the heat collector includes the thermally conductive connector.

5. The lighting device of claim 1, wherein the first surface of the light guide is a light emitting surface comprising reflective optics.

6. The lighting device of claim 1, wherein the lighting device is selected from the group consisting of a tail light, a brake light, a turn light, a center high mount stop lamp, a high level brake lamp, a license plate number lamp, an outline lamp, a headlight, and a direction indicator.

7. The lighting device of claim 1, wherein the light guide includes a reflective material.

8. The lighting device of claim 1 further comprising an air channel between the first and the second surface of the light guide, the air channel dissipating heat generated by the single LESD and the control circuit.

9. The lighting device of claim 1, wherein the light guide includes a thermally conductive material.

10. A method of managing heat generated within a lighting device, the method comprising:

providing a lighting device comprising a first surface and a second surface composed of a thermally conductive substrate material, the lighting device comprising;

a single Light Emitting Semiconductor Device (LESD) operable to radiate light; and

a control circuit mounted between the first surface and the second surface of the lighting device, the control circuit electrically coupled to the single LESD to control operation of the single LESD;

providing an air channel between the first surface and the second surface of the lighting device; and

transferring heat generated by the single LESD and the control circuit through the air channel of the lighting device thereby uniformly distributing heat throughout the lighting device.

11. The method of claim 10, wherein providing the lighting device comprises providing a device selected from the group consisting of a tail light, a brake light, a center high mount stop lamp, a high level brake lamp, a license plate number lamp, an outline lamp, a headlight, and a direction indicator.

12. The method of claim 10, wherein the single LESD is a Light Emitting Diode (LED).

13. The method of claim 10, wherein the single LESD is coupled to the lighting device using a thermally conductive connector.

14. The method of claim 13 further comprising the step of transferring heat generated by the single LESD and the control circuit away from the lighting device through the thermally conductive connector.

15. An exterior vehicle lamp comprising:

a lens and a reflector coupled together comprising a light guide; and

a single Light Emitting Semiconductor Device (LESD) operable to radiate light mounted within the light guide,

wherein the single LESD is mounted within the light guide using a thermally conductive connector, the thermally conductive connector operable to dissipate heat generated by the single LESD.

16. The lamp of claim 15 further comprising an air channel arranged between the lens and the reflector of the light guide, wherein heat generated by the single LESD is transferred through the air channel thereby uniformly distributing heat throughout the tail lamp.

17. The lamp of claim 15, wherein the light guide shields the view of the single LESD.

18. The lamp of claim 15, wherein the light guide comprises a thermally conductive material.

19. The lamp of claim 15, wherein the single LESD is a Light Emitting Diode.

20. The lamp of claim 15 further comprising:

a back plate coupled to the light guide forming an air channel between the light guide and the back plate; and

a control circuit conductively coupled to the single LESD, the control circuit mounted between the back plate and the light guide,

wherein heat generated by the single LESD and the control circuit is transferred through the air channel thereby uniformly distributing heat throughout the tail lamp.