Projecting image display device

• US 6,343,862 B1
• Filed: 11/12/1999
• Issued: 02/05/2002
• Est. Priority Date: 11/20/1998
• Status: Expired due to Term

• Current Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Original Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Inventors: Sawai, Yasumasa, Ishihara, Jun, Ohzawa, Soh, Hayashi, Kohtaro, Ori, Yuichiro
• Primary Examiner(s): Adams, Russell
• Assistant Examiner(s): Cruz, Magda
• Application Number:
  US09/439,168
• Time in Patent Office: 816 Days
• Field of Search: 359/616, 353/1, 353/37, 353/33, 353/31, 353/34, 353/38, 353/98, 353/99, 349/5, 349/7, 349/8
• US Class Current: 353/1
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G02B 3/0062 Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between
• CPC Class Codes: G02B 3/0068 arranged in a single integral body or plate, e.g. laminates or hybrid structures with other optical elements G02B5/1885, G02B17/002, G02B30/27 take precedence
• CPC Class Codes: G02B 3/06 with cylindrical or toric faces
• CPC Class Codes: G03B 21/006 using LCD's
• CPC Class Codes: G03B 21/14 Details
• CPC Class Codes: G03B 21/208 Homogenising, shaping of the illumination light

Abstract

A projecting image display device is disclosed which includes a display and a micro lens array, where the pixels of the display and the micro lens elements each have non symmetric properties in length and width directions. The micro lens concentrates color-separated light onto pixels of a display device so that light does not hit the black matrix. By providing a display having pixels which are not equal in length and width, pixels corresponding to red (R), green (G) and blue (B) can be arranged in a substantially square area, and by providing a micro lens array which has non symmetric properties in length and width, the color separated light can be concentrated onto the non square display pixels.

Claims

1. An optical apparatus comprising:

a light source which is capable of generating light of a plurality of colors;

a display for modulating light from said light source which is incident thereon, said display including a plurality of pixels, each pixel having a height and a width thereof being nonequivalent; and

a micro lens array for receiving light from said light source, either directly or via another optical element, said micro lens array including a plurality of micro lenses, said micro lenses being positioned to focus a portion of said received light onto said display and at least one of said micro lenses having a different optical power along substantially perpendicular height and width directions.

2. An optical apparatus in accordance with claim 1, wherein a ratio of height to width of said pixels of said display is substantially equal to a ratio of optical power of each micro lens unit along said substantially perpendicular height and width directions.

3. An optical apparatus in accordance with claim 1, further comprising a light color separating device for receiving light from said light source, either directly or via another optical element, and for deflecting light of each of said plurality of colors by a different amount, said light color separating device being disposed between said light source and said micro lens array.

4. An optical apparatus in accordance with claim 3, further comprising an optical device disposed between said light source and said light color separating device for receiving light from said light source and for making substantially uniform an intensity distribution of said light received from said light source and for transmitting light having, a substantially uniform distribution to said light color separating device.

5. An optical apparatus in accordance with claim 4, wherein said optical device for making, substantially uniform an intensity distribution of said light received from said light source is an optical integrator.

6. An optical apparatus in accordance with claim 5, wherein said integrator includes at least two lens arrays, each lens array comprising a plurality of lens cells, lens cells of a first of said at least two lens arrays being aligned in a zigzag fashion.

7. An optical apparatus in accordance with claim 5, wherein said integrator includes at least two lens arrays, each lens array comprising a plurality of lens cells, a second of said lens arrays having a plurality of inclined half mirrors positioned at an exit plane thereof, said half mirrors having a belt configuration, said half mirrors being oriented so as to transmit a portion of light incident thereon and reflect a portion of light incident thereon, said portion of light reflected by one of said half mirrors being directed so as to be incident on another one of said half mirrors.

8. An optical apparatus in accordance with claim 3, wherein said display, said light color separating device and said micro lens array are arranged so that light of each of said plurality of colors is focused onto corresponding portions of said plurality of pixels of said display.

9. An optical apparatus in accordance with claim 3, wherein said a light color separating device is a diffraction grating.

10. An optical apparatus in accordance with claim 3, wherein said a light color separating device comprises a dichroic mirror.

11. An optical apparatus in accordance with claim 4, wherein said optical device for making substantially uniform an intensity distribution of said light received from said light source is a kaleidoscope.

12. An optical apparatus in accordance with claim 11, wherein said kaleidoscope is positioned so as to receive light from said light source at a position offset from a center of a light entry plane of said kaleidoscope.

13. An optical apparatus in accordance with claim 4, wherein said optical device for making substantially uniform an intensity distribution of said light received from said light source comprises a two-tier integrator, each tier including two lens arrays, a lens element in said lens arrays of a first tier being smaller than a lens element in said lens arrays of a second tier.

14. An optical apparatus in accordance with claim 4, further comprising a projecting optical system for receiving light modulated by said display and for projecting the light modulated by said display.

15. An optical apparatus in accordance with claim 1, wherein said display is a liquid crystal panel.

16. An optical apparatus in accordance with claim 1, wherein said display is a digital micromirror device.

17. An optical apparatus in accordance with claim 1, wherein each of said micro lens units is separated from others of said micro lens units by a half-mirror, said half-mirror being oriented substantially parallel to an optical axis of said micro lens unit.

18. An optical apparatus in accordance with claim 1, wherein each of said micro lens units is separated from others of said micro lens units by an air gap, said air gap being oriented substantially parallel to an optical axis of said micro lens unit.

19. An optical apparatus in accordance with claim 1, wherein said micro lens array includes a first plurality of substantially parallel cylindrical lens elements and a second plurality of substantially parallel cylindrical lens elements, said first plurality of lens elements being oriented substantially perpendicular to an orientation of said second plurality of lens elements, a spacing pitch of said first plurality of lens elements being different than a spacing pitch of said second plurality of lens elements of said micro lens array.

20. An optical apparatus in accordance with claim 19, wherein a ratio of height to width of said pixels of said display is substantially equal to a ratio of said pitch of said first plurality of lens elements to said pitch of said second plurality of lens elements.

21. An optical apparatus in accordance with claim 1 wherein at least one of the micro lenses produces a focused light spot on the display the focused light spot having a major axis and a minor axis, the major axis being larger than the minor axis, and wherein the major axis is perpendicular to the greater of the height and width of the pixels.

22. An optical apparatus comprising:

a light source which is capable of generating light of a plurality of colors;

a display for modulating light from said light source which is incident thereon, said display including a plurality of pixels, for each pixel, a height and a width thereof being nonequivalent; and

a micro lens array, disposed between said light source and said display, for receiving light from said light source, either directly or via another optical element, and for focusing a portion of said received light onto said display, said micro lens array including a first plurality of substantially parallel cylindrical lens elements and a second plurality of substantially parallel cylindrical lens elements, said first plurality of lens elements being oriented substantially perpendicular to an orientation of said second plurality of lens elements, a spacing pitch of said first plurality of lens elements being different than a spacing pitch of said second plurality of lens elements of said micro lens array.

23. An optical apparatus in accordance with claim 22, wherein a ratio of height to width of said pixels of said display is substantially equal to a ratio of said pitch of said first plurality of lens elements to said pitch of said second plurality of lens elements.

24. An optical apparatus in accordance with claim 23, wherein said pitch of said first plurality of lens elements is substantially equal to said height of said pixels of said display and said pitch of said second plurality of lens elements is substantially equal to said width of said pixels of said display.

25. An optical apparatus in accordance with claim 22, further comprising a light color separating device for receiving light from said light source, either directly or via another optical element, and for deflecting light of each of said plurality of colors by a different amount, said light color separating device being disposed between said light source and said micro lens array.

26. An optical apparatus in accordance with claim 22, wherein the micro lens array produces a plurality of focused light spots on the display, the focused light spots having a major axis and a minor axis, the major axis being larger than the minor axis, and wherein the major axis is perpendicular to the greater of the height and width of the pixels.

27. An optical apparatus comprising:

a light source which is capable of generating light of a plurality of colors;

a light color separating system for receiving light from said light source, either directly or via another optical element, and for deflecting light of each of said plurality of colors along separate optical paths;

a plurality of displays, one display for each of said plurality of separated colors, for modulating light from said light color separating device which is incident thereon, said display including a plurality of pixels, for each pixel, a height and a width thereof being nonequivalent; and

a plurality of micro lens arrays, one micro lens array being disposed between said light color separating device and each of said displays, each micro lens array being for receiving light separated by said light color separating device and for focusing a portion of said received light onto a corresponding display, each micro lens array including a first plurality of substantially parallel cylindrical lens elements and a second plurality of substantially parallel cylindrical lens elements, said first plurality of lens elements being oriented substantially perpendicular to an orientation of said second plurality of lens elements, a spacing pitch of said first plurality of lens elements being different than a spacing pitch of said second plurality of lens elements of said micro lens array.

28. An optical apparatus in accordance with claim 27, further comprising a color light combining element for receiving light modulated by the plurality of displays and for combining said light modulated by the plurality of displays into a combined polychromatic light beam.

29. An optical apparatus in accordance with claim 28, wherein said light combining element comprises a cross dichroic prism.

30. An optical apparatus in accordance with claim 28, further comprising a projecting optical system for projecting the polychromatic light beam.

31. An optical apparatus in accordance with claim 27, wherein said light color separating system includes at least one dichroic mirror and one full reflecting mirror.

32. An optical apparatus in accordance with claim 27, wherein said light color separating system includes a cross dichroic mirror.

33. An optical apparatus in accordance with claim 27, wherein at least one of the plurality of micro lens arrays produces a plurality of focused light spots on one of the plurality of displays, the focused light spots having a major axis and a minor axis, the major axis being larger than the minor axis, and wherein the major axis is perpendicular to the greater of the height and width of the pixels.

34. An optical apparatus comprising:

a light source which is capable of generating light of a plurality of colors;

a display for modulating light from said light source which is incident thereon, said display including a plurality of pixels, said display including a plurality of pixels, for each pixel, a height and a width thereof being non equivalent; and

a micro lens array, disposed between said light source and said display, for receiving light from said light source, either directly or via another optical element, and for focusing a portion of said received light onto said display, said micro lens array including a first plurality of substantially parallel cylindrical lens elements and a second plurality of substantially parallel cylindrical lens elements, said first plurality of lens elements being oriented substantially perpendicular to an orientation of said second plurality of lens elements, a spacing pitch of said first plurality of lens elements being substantially the same as a spacing pitch of said second plurality of lens elements of said micro lens array, an optical power of each lens element of said first plurality of lens elements being different than an optical power of each lens element of said second plurality of lens elements.

35. An optical apparatus in accordance with claim 34, wherein a ratio of height to width of said pixels of said display is substantially equal to a ratio of said optical power of each lens element of said first plurality of lens elements to said optical power of each lens element of said second plurality of lens elements.

36. An optical apparatus in accordance with claim 34, further comprising, a light color separating device for receiving light from said light source, either directly or via another optical element, and for deflecting light of each of said plurality of colors by a different amount, said light color separating device being disposed between said light source and said micro lens array.

37. An optical apparatus in accordance with claim 34, wherein the micro lens array produces a plurality of focused light spots on the display, the focused light spots having a major axis and a minor axis, the major axis being larger than the minor axis, and wherein the major axis is perpendicular to the greater of the height and width of the pixels.

38. An optical apparatus comprising:

a light source which is capable of generating light of a plurality of colors;

a reflective display for receiving light from said light source, for modulating said light to provided modulated light and for reflecting said modulated light, said display including a plurality of pixels, for each pixel, a height and a width thereof being nonequivalent; and

a micro lens array, disposed between said light source and said display, including a plurality of micro lens units, for receiving received light from said light source and for focusing a portion of said received light onto said display, an optical power of each micro lens unit being different along substantially perpendicular height and width directions.

39. An optical apparatus in accordance with claim 38, further comprising a light color separating device for receiving light from said light source, either directly or via another optical element, and for deflecting light of each of said plurality of colors by a different amount, said light color separating device being disposed between said light source and said micro lens array and providing said received light to said micro lens array.

40. An optical apparatus in accordance with claim 39, wherein said light color separating device is a dichroic prism.

41. An optical apparatus in accordance with claim 40, wherein said dichroic prism is adapted to receive said received light from said light source and to deflect said received into component light of each of said plurality of colors by a different amount, said dichroic prism being further adapted to receive modulated light which is modulated and reflected by said display and to transmit said modulated light from said display without deflecting said modulated light into component modulated light of each of said plurality of colors by a different amount.

42. An optical apparatus in accordance with claim 39, further comprising an optical device disposed between said light source and said light color separating device for receiving light from said light source and for making substantially uniform an intensity distribution of said light received from said light source and for transmitting light having a substantially uniform distribution to said light color separating device.

43. An optical apparatus in accordance with claim 38, wherein a ratio of height to width of said pixels of said display is substantially equal to a ratio of optical power of each micro lens unit along said substantially perpendicular height and width directions.

44. An optical apparatus in accordance with claim 38, wherein said micro lens array includes a birefringent material so that said micro lens array has an optical power for light received from said light source so as to be capable of focusing a portion of said received light onto said display and said micro lens array has substantially zero optical power for light incident thereon which is reflected from said display.

45. An optical apparatus in accordance with claim 38, wherein the micro lens units produce a focused light spot on the display, the focused light spot having a major axis and a minor axis, the major axis being larger than the minor axis, and wherein the major axis is perpendicular to the greater of the height and width of the pixels.