Display device using a light guide for exterior automotive lighting

• US 6,305,813 B1
• Filed: 08/11/1999
• Issued: 10/23/2001
• Est. Priority Date: 08/11/1999
• Status: Expired due to Term

• Current Assignee: North American Lighting Incorporated (Koito Manufacturing Company Limited)
• Original Assignee: North American Lighting Incorporated (Koito Manufacturing Company Limited)
• Inventors: Jiao, Jianzhong, Lekson, Matthew Andrew
• Primary Examiner(s): O'Shea, Sandra
• Assistant Examiner(s): ZEADE, BERTRAND
• Application Number:
  US09/372,567
• Time in Patent Office: 804 Days
• Field of Search: 362/31, 362/26, 362/27, 362/511, 385/146
• US Class Current: 362/625
• CPC Class Codes: B60Q 1/302 mounted in the vicinity, e.g. in the middle, of a rear window
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 43/15 Strips of light sources
• CPC Class Codes: F21S 43/237 rod-shaped
• CPC Class Codes: F21S 43/239 plate-shaped
• CPC Class Codes: F21S 43/245 emitting light from one or more of its major surfaces
• CPC Class Codes: F21S 43/249 with two or more light sources being coupled into the light guide
• CPC Class Codes: F21S 43/26 Refractors, transparent cover plates, light guides or filters not provided in groups F21S43/235 - F21S43/255
• CPC Class Codes: G02B 6/0048 with stepwise taper

Abstract

A display device is provided for providing lighting in exterior and interior lighting applications, such as for center high mount stop lights (CHMSL) and other automotive lighting applications. The display device uses a light guide having light couplers on a light source end for receiving light from at least one light source. The light guide extends from the light source end with a light emitting surface and a light guide surface opposite the light emitting surface. The light emitting surface and the light guide surface extend in a direction substantially parallel to the direction of the light received from the light source. The light guide surface has a plurality of surface sections extending at angles relative to one another. The surface sections may be angled at alternating sections direct light towards the light emitting surface using total internal reflection.

Claims

1. A display device comprising:

at least one light source operable to radiate a light in a first direction;

at least one light coupler adjacent the at least one light source to receive the light, the at least one light coupler being operable to distribute the light in the first direction;

a light guide comprising a substrate material, the light guide having;

a light source end adjacent the at least one light coupler to receive the distributed light;

a light emitting surface extending from the light source end substantially along the first direction; and

a light guide surface extending from the light source substantially along the first direction, the light guide surface being opposite the light emitting surface; and

the light guide surface comprising a plurality of first surface sections, the first surface sections extending substantially non-parallel to the light emitting surface and each first surface section separated by at least one of a plurality of second surface sections, the second surface sections extending substantially non-parallel to the light emitting surface, the first surface sections extending at different angles from the second surface sections, at least one of the first and second surface sections being at a reflective angle to provide reflection of the light generated by the light source at the at least one first and second surface sections, the reflective angle of the at least one of the first and second surface sections further providing for refraction of the reflected light at the light emitting surface with a light distribution spread in a second direction.

2. The display device of claim 1 wherein:

at least one of the first surface sections extending at a second reflective angle from the light source end, the second reflective angle causing the light to reflect such that the reflected light from the at least one of the first surface sections diverges from the reflected light from the second surface sections.

3. The display device of claim 1 wherein:

at least one of the first surface sections extending at a second reflective angle from the light source end, the second reflective angle causing the light to reflect such that the reflected light from the at least one of the first surface sections converges from the reflected light from the second surface sections.

4. The display device of claim 1 wherein the substrate material may be a material selected from the group consisting of:

acrylic, polycarbonate, plastic, or glass.

5. The display device of claim 1 wherein the at least one light source includes light source devices selected from the group consisting of:

light emitting diodes (LEDs), fiberoptic device outputs, tubular light sources, and incandescent lamps.

6. The display device of claim 1 wherein the at least one light coupler includes light coupling devices selected from the group consisting of:

a fresnel lens, a substantially round ashperic lens, a substantially round spheric lens, and a substantially elliptical aspheric lens.

7. The display device of claim 1 comprising:

a plurality of light couplers arranged linearly; and

a plurality of light sources arranged linearly, each light source being positioned adjacent a corresponding light coupler.

8. The display device of claim 1 wherein the reflective angle is approximately 150 degrees.