Vehicular light guides and assemblies with uniform illumination

Patent metadata

Field	Value
Publication number	US-9464785-B2
Application number	US-201313736395-A
Country	US
Kind code	B2
Filing date	Jan 8, 2013
Priority date	Jan 8, 2013
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

A light guide is provided that includes a light chamber defined by isotropically luminant top, bottom, and back surfaces, and a front surface having a translucent lens. The light guide also includes a reflective diaphragm within the chamber that defines a top gap between the diaphragm and the top surface, and a bottom gap between the diaphragm and the bottom surface. The light guide further includes an LED light source located between the diaphragm and the back surface of the chamber. The light guide may also be configured with a front surface having a partially transmissive lens and no reflective diaphragm. A vehicle lighting assembly is also provided that includes a plurality of interconnected light chamber sections comprising light guides.

First claim

We claim:

1. A light guide, comprising:
a light chamber defined by isotropic, light-scattering top, bottom, and back surfaces, a front surface having a translucent lens and a length;
a mirror-like reflective diaphragm within the chamber that defines a top gap between the diaphragm and the top surface, and a bottom gap between the diaphragm and the bottom surface, and spans the length of the chamber, wherein the diaphragm is spaced from the translucent lens, about one third of the distance between the lens and the back surface; and
an LED light source located between the diaphragm and the back surface of the chamber,
wherein the light chamber is further defined by a substantially constant cross-sectional area across the length of the chamber, and is configured in the shape of a rectangular cuboid having two opposed, parallel ends, and, further,
wherein the ratio between the total height of the gaps and the distance between the top and bottom surfaces of the light chamber is approximately 1:4 to 1:9,
and further wherein the LED light source is located at one of the opposed ends of the light chamber and oriented to emanate incident light toward the other of the opposed ends of the light chamber such that only a portion of the incident light strikes the diaphragm, and further wherein the rectangular cuboid has a length that spans the longest axis of the cuboid and the two opposed, parallel ends are at the respective ends of the length.

2. The light guide according to claim 1 , wherein the ratio between the total height of the gaps and the distance between the top and bottom surfaces of the light chamber is approximately 1:9.

3. The light guide according to claim 1 , wherein the light chamber encloses a substantially gaseous medium.

4. The light guide according to claim 1 , wherein the light chamber is arranged in a vehicular tail-light configuration.

5. The light guide according to claim 1 , wherein the LED light source is a single LED light source within the chamber.

6. A lighting assembly, comprising:
a plurality of interconnected, non-isolated light chamber sections, each section comprising:
a light chamber defined by isotropic, light-scattering top, bottom, and back surfaces, a front surface having a translucent lens, and a length;
a mirror-like reflective diaphragm within the chamber defining a gap between the diaphragm and the interior surfaces that spans the length of the chamber, wherein the diaphragm is spaced from the translucent lens, about one third of the distance between the lens and a back surface of the chamber; and
an LED light source within the chamber,
wherein the ratio between the total height of the gap and the distance between top and bottom interior surfaces of the light chamber is approximately 1:4 to 1:9,
wherein the light chamber is further defined by a substantially constant cross-sectional area across the length of the chamber and is configured in the shape of a rectangular cuboid having two opposed, parallel ends,
wherein the LED light source is located at one of the opposed ends of the light chamber and oriented to emanate incident light toward the other of the opposed ends of the light chamber such that only a portion of the incident light strikes the diaphragm,
wherein the rectangular cuboid has a length that spans the longest axis of the cuboid and the two opposed, parallel ends are at the respective ends of the length, and
further wherein the front surface of each section is not shared by another section.

7. The lighting assembly according to claim 6 , wherein the light chamber encloses a substantially gaseous medium.

8. The lighting assembly according to claim 6 , wherein the light chamber is arranged in a vehicular tail-light configuration.

9. The lighting assembly according to claim 6 , wherein the LED light source is a single LED light source within the chamber.

10. A light guide, comprising:
a rectangularly-shaped light chamber having isotropic, light-scattering interior surfaces, a translucent lens and a length;
a mirror-like reflective diaphragm within the chamber defining a gap between the diaphragm and the interior surfaces that spans the length of the chamber, wherein the diaphragm is spaced from the translucent lens, about one third of the distance between the lens and a back surface of the chamber; and
a single LED source located at a long end of the chamber oriented to emanate incident light toward the other long end that scatters from the interior surfaces, passes through the gap, and exits the chamber through the lens,
wherein the ratio between the total height of the gap and the distance between top and bottom interior surfaces of the light chamber is approximately 1:4 to 1:9, and
further wherein only a portion of the incident light strikes the diaphragm.

11. The light guide according to claim 10 , wherein the ratio between the total height of the gap and the distance between top and bottom interior surfaces of the light chamber is approximately 1:9.

12. The light guide according to claim 10 , wherein the light chamber encloses a substantially gaseous medium.

13. The light guide according to claim 10 , wherein the light chamber is arranged in a vehicular tail-light configuration.

14. The light guide according to claim 10 , wherein the diaphragm comprises metal constituents.

Assignees

• Ford Global Tech Llc

Inventors

• Kumar Arun
• Dassanayake Mahendra Somasara
• Miller Steven Darrell

Classifications

• F21V5/04

  of lens shape · CPC title

• F21V2200/40

  of hollow light guides · CPC title

• F21S43/237

  rod-shaped · CPC title

• F21Y2115/10

  Light-emitting diodes [LED] · CPC title

• G02B6/0051

  Diffusing sheet or layer · CPC title