Integrated front light solution

• US 8,654,061 B2
• Filed: 12/23/2008
• Issued: 02/18/2014
• Est. Priority Date: 02/12/2008
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Mienko, Marek, Xu, Gang, Bita, Ion, Wang, Lai, Gruhlke, Russell W.
• Primary Examiner(s): Liang, Regina
• Application Number:
  US12/343,279
• Publication Number:
  US 20090201301A1
• Time in Patent Office: 1,883 Days
• Field of Search: 345/102, 362/600, 362/606, 362608-628
• US Class Current: 345/102
• CPC Class Codes: G02B 6/0011 the light guides being planar or of plate-like form
• CPC Class Codes: G02B 6/0016 Grooves, prisms, gratings, scattering particles or rough surfaces
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/002 by shaping at least a portion of the light guide, e.g. with collimating, focussing or diverging surfaces
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G09G 3/3466 based on interferometric effect

Abstract

An integrated illumination apparatus includes a light injection portion having a first end for receiving light from a light source. The light injection portion includes material that supports propagation of said light along the length of the light injection portion. Turning microstructure is disposed on a first side of the light injection. The turning microstructure is configured to turn at least a substantial portion of light incident on the first side and to direct the portion of the light out a second opposite side of the light injection portion. A slit is disposed along the length of the light injection portion. The slit forms an optical interface on the second opposite side of the light injection portion that provides total internal reflection for light propagating along the length of the light injection portion to be guided therein. The optical interface further transmits light turned by said turning microstructure. A light distribution portion is disposed with respect to the slit to receive the light turned by said turning microstructure and transmitted out of the second side of the light injection portion and through said slit. At least one bridge is disposed between light injection portion and the light distribution portion. The bridge mechanically connects the light injection portion to the light distribution portion.

Claims

1. An integrated illumination apparatus comprising:

a light injection portion having a first end for receiving light from a light source located at the first end of the light injection portion, wherein the light injection portion has a length, said light injection portion comprising material that supports propagation of said light along the length of the light injection portion towards a second opposite end;

turning microstructure disposed on a first side of the light injection portion, the turning microstructure configured to turn at least a substantial portion of light incident on the first side and to direct the portion of the light towards a second opposite side of the light injection portion, wherein a width dimension of the light injection portion extends from the first side to the second side orthogonal to the length of the light injection portion;

a slit disposed along the length of the light injection portion, the slit forming an optical interface on the second opposite side of the light injection portion that provides total internal reflection for light propagating along the length of the light injection portion to be guided therein, said optical interface further transmitting light turned by said turning microstructure, the slit including two sidewalls, one or both of the sidewalls including one or both of;

a plurality of curved light control features defined by curves extending in a length dimension of the slit, and one or more curved light control features defined by curves extending substantially in a thickness dimension of the light injection portion, the thickness dimension orthogonal to both the length and the width dimension of the light injection portion;

a light distribution portion disposed with respect to the slit to receive the light turned by said turning microstructure and transmitted out of the second side of the light injection portion and through said slit; and

at least one bridge disposed between light injection portion and the light distribution portion and mechanically connecting the light injection portion to the light distribution portion.

2. The integrated illumination apparatus of claim 1, wherein the light injection portion, the light distribution portion, and the bridge comprise a monolithic film.

3. The integrated illumination apparatus of claim 1, wherein the at least one bridge is disposed proximal to the first end of the light injection portion.

4. The integrated illumination apparatus of claim 1, wherein the at least one bridge is disposed proximal to the second opposite end of the light injection portion.

5. The integrated illumination apparatus of claim 1, wherein the at least one bridge comprises two bridges disposed proximal to the first end and the second opposite end of the light injection portion.

6. The integrated illumination apparatus of claim 1, wherein the turning microstructure comprises a plurality of faceted features formed directly into of the light injection portion.

7. The integrated illumination apparatus of claim 6, wherein the faceted features comprise a plurality of grooves formed directly into the light injection portion.

8. The integrated illumination apparatus of claim 7, wherein the grooves comprise a plurality of triangular grooves having substantially triangular cross-sections.

9. The integrated illumination apparatus of claim 1, further comprising an additional slit displaced from the slit laterally along the length of the integrated illumination apparatus, and disposed with respect to the bridge to provide total internal reflection for a portion of light that would have otherwise leaked into the bridge.

10. The integrated illumination apparatus of claim 9, wherein the additional slit is disposed proximal to the bridge and has substantially the same length as the width of the bridge.

11. The integrated illumination apparatus of claim 1, wherein the light control features control the angular direction of the light transmitted from the light injection portion into the light distribution portion.

12. The integrated illumination apparatus of claim 11, wherein the light control features comprise a convex-shaped feature formed on at least one of the side walls.

13. The integrated illumination apparatus of claim 11, wherein the light control features comprise a cylindrical lens.

14. The integrated illumination apparatus of claim 1, wherein the light control features increase collimation of the transmitted light.

15. The integrated illumination apparatus of claim 1, wherein the light control features increase in-plane collimation of the transmitted light.

16. The integrated illumination apparatus of claim 1, wherein the light control features increase out-of-plane collimation of the transmitted light.

17. The integrated illumination apparatus of claim 1, wherein the light control features increase divergence of the transmitted light.

18. The integrated illumination apparatus of claim 17, wherein the light control features comprise a plurality of concave-shaped features formed on at least one of the side walls.

19. The integrated illumination apparatus of claim 1, wherein the light control features deflect the transmitted light.

20. The integrated illumination apparatus of claim 19, wherein the light control features comprise a plurality of sawtooth-shaped features formed on at least one of the side walls, wherein the sawtooth-shaped features comprise a substantially uniform cross section along the thickness direction of the slit.

21. The integrated illumination apparatus of claim 19, wherein the light control features comprise microprisms.

22. The integrated illumination apparatus of claim 19, wherein the light control features change the color of the light transmitted from the light injection portion into the light distribution portion.

23. The integrated illumination apparatus of claim 1, further comprising a light control insert placed in the slit.

24. The integrated illumination apparatus of claim 23, wherein the light control insert comprises a bar.

25. The integrated illumination apparatus of claim 24, wherein the light control insert comprises a uniform rectangular cross section along the length direction of the slit.

26. The integrated illumination apparatus of claim 23, wherein the light control insert controls the angular direction of the light transmitted from the light injection portion into the light distribution portion.

27. The integrated illumination apparatus of claim 2, wherein the light control insert comprises a uniform flat surface along the length direction of the slit.

28. The integrated illumination apparatus of claim 23, wherein the light control insert increases collimation of the transmitted light.

29. The integrated illumination apparatus of claim 23, wherein the light control insert increases divergence of the transmitted light.

30. The integrated illumination apparatus of claim 23, wherein the light control insert redirects the transmitted light.

31. The integrated illumination apparatus of claim 23, wherein the light control insert changes the color of the light transmitted from the light injection portion into the light distribution portion.

32. The integrated illumination apparatus of claim 1, wherein the light injection portion further comprises at least one reflective surface disposed with respect to a side of the light injection portion to receive light transmitted therethrough.

33. The integrated illumination apparatus of claim 1, wherein the light distribution portion is disposed with respect to a plurality of spatial light modulators to illuminate the plurality of spatial light modulators.

34. The integrated illumination apparatus of claim 33, wherein the plurality of spatial light modulators comprises an array of interferometric modulators.

35. The integrated illumination apparatus of claim 33, further including a substrate comprising the plurality of spatial light modulators.

36. The integrated illumination apparatus of claim 35, wherein the light injection portion is at least in part laminated to the substrate via an adhesive.

37. The integrated illumination apparatus of claim 35, wherein the light injection portion is at least in part disposed with respect to the substrate via an air gap.

38. The integrated illumination apparatus of claim 1, further comprising:

display elements, wherein the light distribution portion is configured to illuminate the display elements;

a processor that is configured to communicate with said display elements, said processor being configured to process image data; and

a memory device that is configured to communicate with said processor.

39. The integrated illumination apparatus of claim 38, further comprising a driver circuit configured to send at least one signal to the display elements.

40. The integrated illumination apparatus of claim 39, further comprising a controller configured to send at least a portion of the image data to the driver circuit.

41. The integrated illumination apparatus of claim 38, further comprising an image source module configured to send said image data to said processor.

42. The integrated illumination apparatus of claim 41, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

43. The integrated illumination apparatus of claim 38, further comprising an input device configured to receive input data and to communicate said input data to said processor.

44. The integrated illumination apparatus of claim 1, wherein both sidewalls of the slit include one or more curved light control features.

45. The integrated illumination apparatus of claim 44, wherein both sidewalls of the slit include convex light control features curving outwards toward one another.

46. The integrated illumination apparatus of claim 45, wherein the convex light control features are configured to collimate light.

47. An illumination apparatus comprising:

means for injecting light having means for receiving light from a means for emitting light located at a first end of the means for injecting light, said light injecting means comprising means for supporting propagation of said light along a length of the light injecting means towards a second end of said light injecting means;

means for turning light disposed on a first side of the light injecting means, the light turning means configured to turn at least a substantial portion of light incident on the first side and to direct the portion of the light towards a second opposite side of the light injecting means;

means for providing total internal reflection for light propagating along the length of the light injecting means to be guided therein, said total internal reflection providing means disposed along the length of the light injecting means on the second opposite side of the light injecting means, said total internal reflection providing means further transmitting light turned by said light turning means, wherein a width dimension of the light injecting means extends from the first side of the light injecting means to the second side of the light injecting means, the total internal reflection providing means having one or both of;

a plurality of curved light control features defined by curves extending in a length dimension of the light injecting means, and one or more curved light control features defined by curves extending substantially in a thickness dimension of the light injecting means, the thickness dimension orthogonal to both the length and the width dimension of the light injecting means;

means for distributing light disposed with respect to the total internal reflection providing means to receive the light from said light turning means and transmitted out of the second side of the light injecting means and through said total internal reflection providing means; and

means for mechanically connecting disposed between and mechanically connecting the light injecting means and the light distribution means.

48. The illumination apparatus of claim 47, wherein said light injecting means comprises a light injection portion or said light receiving means comprises the first end of said light injecting means and said second end toward which said light propagates along the length of said light injecting means comprises a second opposite end of said light injecting means or said light emitting means comprises a light source or said light propagation supporting means comprises material that supports propagation of said light or said light turning means comprises turning microstructures or said total internal reflection providing means comprises a slit or an optical interface or said light distributing means comprises a light distribution portion or said mechanically connecting means comprises at least one bridge.