Bireflective lens element

• US 6,097,549 A
• Filed: 08/12/1998
• Issued: 08/01/2000
• Est. Priority Date: 08/12/1997
• Status: Expired due to Term

• Current Assignee: Intellectual Discovery Co., Ltd.
• Original Assignee: Breault Research Organization Inc.
• Inventors: Jenkins, David, Pagano, Robert, Cote, Marie, Griffin, Joseph A.
• Primary Examiner(s): Sugarman, Scott J.
• Application Number:
  US09/133,178
• Time in Patent Office: 720 Days
• Field of Search: 359/726, 359/732, 359/730, 359/731, 359/725, 362/293, 362/321, 362/294, 362/459, 362/517-522
• US Class Current: 359/726
• CPC Class Codes: B60Q 1/302 mounted in the vicinity, e.g. in the middle, of a rear window
• CPC Class Codes: F21S 41/322 the reflector using total internal reflection
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• 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 43/247 with a single light source being coupled into the light guide
• CPC Class Codes: F21S 43/249 with two or more light sources being coupled into the light guide
• CPC Class Codes: F21S 43/315 using total internal reflection
• CPC Class Codes: F21S 43/40 characterised by the combination of reflectors and refractors
• CPC Class Codes: F21V 5/008 Combination of two or more successive refractors along an optical axis
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00
• CPC Class Codes: G02B 3/08 with discontinuous faces, e.g. Fresnel lens diffractive Fresnel lenses G02B5/1876
• CPC Class Codes: G02B 6/0021 for housing at least a part of the light source, e.g. by forming holes or recesses
• CPC Class Codes: G02B 6/0023 provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• CPC Class Codes: G02B 6/0048 : with stepwise taper

Abstract

A bireflective lens element comprising a light input surface and a direct transmitting area communicating with the light input surface. A light source is disposed adjacent to the light input surface for projecting light into the lens element to create a light emitting assembly. A first portion of input light is directed through the lens elements in a first predetermined pattern. A primary and a secondary reflecting area is between the light input surface and an illumination surface surrounding the direct light transmitting area. A second portion of input light is redirected through the lens element to the illumination surface in a second predetermined pattern. Specifically, the secondary reflective area has a plurality of extracting facets extending inwardly into the secondary reflective area for intercepting light from the primary reflective area. The first predetermined pattern combines with the second predetermined pattern to output light from the illumination surface in a substantially uniform pattern covering the broad area of the lens element.

Claims

1. A bireflective lens element comprising:

a light input surface,

a direct light transmitting area defining a first section of said lens element and communicating with said light input surface to direct a first portion of input light through said lens element in a first predetermined pattern illuminating said first section of said lens element,

an illumination surface extending from said direct light transmitting area and substantially surrounding said direct light transmitting area to define a second section of said lens element, and

a primary and a secondary reflecting area disposed between said light input surface and said illumination surface to redirect a second portion of input light through said lens element toward said illumination surface in a second predetermined pattern illuminating said second section of said lens element, wherein said first and second portions of the input light create uniform illumination over the lens element.

2. An assembly as set forth in claim 1 wherein said direct transmitting area comprises a substantially flat area defining a base of said primary reflective area.

3. An assembly as set forth in claim 2 wherein said flat area includes a lens for collimating light directly through said lens element.

4. An assembly as set forth in claim 2 wherein said primary reflective area comprises a substantially curved surface extending from said flat base area to said illumination surface for redirecting said second portion of input light from said light input surface toward said secondary reflecting area.

5. An assembly as set forth in claim 2 wherein said primary reflective area comprises a substantially cone shaped surface extending from said flat base area to said illumination surface for redirecting said second portion of input light from said light input surface toward said secondary reflecting area.

6. An assembly as set forth in claim 1 wherein said secondary reflective area includes a plurality of extracting facets extending inwardly into said secondary reflective area for intercepting said second portion of input light from said primary reflective area and redirecting said light toward said illumination surface.

7. An assembly as set forth in claim 6 wherein said facets are spaced apart by adjacent step downs which interconnect a trailing edge of a facet to a leading edge of an adjoining facet.

8. An assembly as set forth in claim 6 wherein said facets are spaced apart by adjacent flat planar surfaces.

9. An assembly as set forth in claim 6 wherein said facets include a substantially curved reflective surface for redirecting said second portion of input light toward said illumination surface.

10. An assembly as set forth in claim 6 wherein said secondary reflective area is substantially rectangular defining said front illumination surface and said facets are divided into discreet pie-shaped regions.

11. An assembly as set forth in claim 10 wherein said primary reflective area is centrally disposed within said rectangular secondary reflective area.

12. An assembly as set forth in claim 1 further including an array of light dispersing projections positioned adjacent said illumination surface for assisting in dispersing and redirecting said second portion of input light from said bireflective lens a element.

13. An assembly as set forth in claim 12 wherein said light dispersing projections comprise an array of pillow lenses for dispersing said input light.

14. An assembly as set forth in claim 13 wherein said lens element is tilted upwardly with respect to said pillow lenses.

15. An assembly as set forth in claim 13 wherein said pillow lenses are an integral part of said secondary reflective area thereby forming said illumination surface.

16. An assembly as set forth in claim 1 further including a transition area for joining two bireflective lens elements and creating a common illumination surface.

17. An assembly as set forth in claim 2 further including a plurality of primary reflective areas to constitute revolved curved surfaces separated by circumferential facets for redirecting said second portion of input light into said secondary reflective area.

18. A light emitting assembly for use in a vehicle comprising,

a bireflective lens element including a light input surface and a light source adjacent to said light input surface for projecting light into said lens element,

a direct light transmitting area defining a first section of said lens element and communicating with said light input surface to direct a first portion of input light through said lens element in a first predetermined pattern illuminating said first section of said lens element,

an illumination surface extending from said direct light transmitting area and substantially surrounding said direct light transmitting area to define a second section of said lens element, and

a primary and secondary reflective area disposed between said light input surface and said illumination surface to redirect a second portion of input light from said light input surface toward said illumination surface in a second predetermined pattern illuminating said second section of said lens element, wherein said first and second portions of said input light create uniform illumination over the lens element.

19. An assembly as set forth in claim 18 wherein said direct transmitting area comprises a substantially flat area defining a base of said primary reflective area.

20. An assembly as set forth in claim 19 wherein said primary reflective area comprises a substantially curved surface extending from said flat base area to said illumination surface for redirecting said second portion of input light from said light input surface toward said secondary reflecting area.

21. An assembly as set forth in claim 18 wherein said secondary reflective area includes a plurality of extracting facets extending inwardly into said secondary reflective area for intercepting said second portion of input light from said primary reflective area and redirecting said light toward said illumination surface.

22. An assembly as set forth in claim 21 wherein said facets include a substantially parabolic reflective surface for redirecting said second portion of input light toward said illumination surface.

23. An assembly as set forth in claim 18 further including an array of light dispersing projections positioned adjacent said illumination surface for assisting in dispersing and redirecting said second portion of input light from said bireflective lens element.

24. An assembly as set forth in claim 18 wherein said light source includes a light emitting diode.

25. An assembly as set forth in claim 24 further including mounting posts for aligning and positioning said lens element with respect to said light emitting diode.

26. A light emitting assembly for use in a vehicle comprising,

a bireflective lens element including a primary reflective area and a secondary reflective area,

said primary reflective area redirects light through said lens element and into said secondary reflective area in a predetermined pattern,

said secondary reflective area includes a plurality of extracting facets extending inwardly into said secondary reflective area for intercepting light from said primary reflective area, and

said facets each include a substantially curved surface for redirecting light from said primary reflective area outwardly away from said bireflective lens element to an illumination surface.

27. An assembly as set forth in claim 26 wherein said facets are spaced apart by adjacent step downs which interconnect a trailing edge of a facet to a leading edge of an adjoining facet.

28. An assembly as set forth in claim 26 wherein said facets are spaced apart by adjacent flat planar surfaces.

29. An assembly as set forth in claim 26 further including a direct transmitting area for directing light through said lens element in a predetermined pattern different from said pattern of said secondary reflective area.

30. An assembly as set forth in claim 29 wherein said direct transmitting area comprises a substantially flat area defining a base of said primary reflective area.

31. An assembly as set forth in claim 30 further including a light source adjacent to said flat area.

32. An assembly as set forth in claim 26 wherein said primary reflective area comprises a substantially curved surface extending from said flat base area to said illumination surface.