LIGHT CONFINEMENT USING DIFFUSERS

• US 20100098377A1
• Filed: 05/27/2009
• Published: 04/22/2010
• Est. Priority Date: 10/16/2008
• Status: Abandoned Application

• Current Assignee: Oree, Inc.
• Original Assignee: Oree, Inc.
• Inventors: Meir, Noam
• Application Number:
  US12/472,993
• Publication Number:
  US 20100098377A1
• Time in Patent Office: Days
• US Class Current: 385/28
• CPC Class Codes: G02B 6/0015 provided on the surface of the light guide or in the bulk of it

Abstract

An illumination structure includes a waveguide, a discrete light source embedded within the waveguide, and a mode-conversion reflector. The mode-conversion reflector converts at least some unconfined modes from the light source into confined modes that propagate fully within the waveguide.

Claims

1. An illumination structure comprising:

a waveguide;

a discrete light source embedded therein; and

a mode-conversion reflector for converting at least some unconfined modes from the light source into confined modes that propagate fully within the waveguide.

2. The structure of claim 1 wherein the mode-conversion reflector is a diffuser.

3. The structure of claim 1 wherein the discrete light source is a top-emitting LED.

4. The structure of claim 1 wherein the waveguide comprises in-coupling, concentration, propagation, and out-coupling regions.

5. The structure of claim 1 wherein the mode-conversion reflector is disposed on a surface of the waveguide opposite an emission region of the light source.

6. The structure of claim 1 wherein about 75% of light emitted by the light source is retained within the waveguide.

7. The structure of claim 5 further comprising a second mode-conversion reflector surrounding the light source.

8. The structure of claim 7 wherein about 85% of light emitted by the light source is retained within the waveguide.

9. The structure of claim 7 wherein the emission region has an area smaller than an area of the of the first mode-conversion reflector, and the area of the first mode-conversion reflector is smaller than an area of the second mode-conversion reflector.

10. The structure of claim 1 the waveguide has an entrance aperture and the light source has an emitting area, the entrance aperture and the emitting area being approximately equal in size.

11. The structure of claim 10 wherein the entrance aperture is surrounded by mode-conversion reflectors.

12. An illumination structure comprising:

a waveguide having an entrance aperture;

a discrete light source having an emission area substantially conforming to the entrance aperture; and

one or more mode-conversion reflectors surrounding the entrance aperture.

13. The structure of claim 12 wherein (i) the waveguide has a refractive index and (ii) the light source is attached to the waveguide by means of an adhesive having a refractive index substantially matching the refractive index of the waveguide.

14. The structure of claim 12 wherein the emission area of the light source is attached to the entrance aperture of the waveguide through an anti-reflective coating.

15. An illumination structure comprising:

a waveguide having an entrance aperture;

one or more mode-conversion reflectors surrounding the entrance aperture;

a discrete light source; and

an optical element for focusing light from the light source onto the entrance aperture.

16. The structure of claim 15 wherein the optical element is a refractive lens.

17. The structure of claim 15 wherein the optical element is a diffractive lens.

18. The structure of claim 15 wherein the optical element is integral with the light source, the light source emitting light within a narrow light-distribution angle.

19. The structure of claim 15 further comprising a mode-conversion reflector for converting at least some unconfined modes from the light source into confined modes that propagate fully within the waveguide, the mode-conversion reflector being disposed on a surface of the waveguide opposite an emission region of the light source.