Six color display apparatus having increased color gamut

• US 20040070736A1
• Filed: 10/11/2002
• Published: 04/15/2004
• Est. Priority Date: 10/11/2002
• Status: Active Grant

• Current Assignee: IMAX Theatres International Limited (IMAX Corporation)
• Original Assignee: Eastman Kodak Company
• Inventors: Zolla, Robert J., Roddy, James E., Blish, Nelson A., Horvath, Louis S.
• Granted Patent: US 6,769,772 B2
• Time in Patent Office: Days
• US Class Current: 353/31
• CPC Class Codes: G03B 21/00 Projectors or projection-type viewers; Accessories therefor devices for changing pictures G03B23/00
• CPC Class Codes: H04N 9/3158 for controlling the spectrum
• CPC Class Codes: H04N 9/3188 Scale or resolution adjustment scaling in general G06T3/40; resolution modifying circuits for displays in general G09G5/391

Abstract

A display system (10) for digital color images using six color light sources (12) or two or more multicolor LED arrays (212, 213) or OLEDs (220, 222) to provide an expanded color gamut. Apparatus (10) uses two or more spatial light modulators (20, 21), which may be cycled between two or more color light sources (12) or LED arrays (212, 213) to provide a six-color display output. Pairing of modulated colors using relative luminance helps to minimize flicker effects.

Claims

1. An apparatus for displaying a color image from digital data, the apparatus comprising:

(a) a first modulation system for providing a first modulated beam, said first modulation system comprising;

(a1) a first spatial light modulator for modulating a first incident light beam in order to form said first modulated beam according to said digital data;

(a2) a first light source for providing a first color beam as said first incident light beam;

(a3) a second light source for providing a second color beam as said first incident light beam;

(a4) a third light source for providing a third color beam as said first incident light beam;

(b) a second modulation system for providing a second modulated beam, said second modulation system comprising;

(b1) a second spatial light modulator for modulating a second incident light beam in order to form said second modulated beam according to said digital data;

(b2) a fourth light source for providing a fourth color beam as said second incident light beam;

(b3) a fifth light source for providing a fifth color beam as said second incident light beam;

(b4) a sixth light source for providing a sixth color beam as said second incident light beam; and

(c) an optical combiner for directing said first modulated beam and said second modulated beam for projection onto a surface by a projection lens.

2. An apparatus according to claim 1 wherein said first light source comprises a laser.

3. An apparatus according to claim 1 wherein said first light source comprises an LED.

4. An apparatus according to claim 1 wherein said first spatial light modulator is from the set consisting of a reflective liquid crystal display device, a transmissive liquid crystal display device, a digital micromirror device.

5. An apparatus according to claim 1 wherein said first and second light sources are selected from the group consisting of red, green, blue, blue-green, violet, and yellow-green color light sources.

6. An apparatus according to claim 1 wherein said optical combiner comprises a dichroic surface.

7. An apparatus according to claim 1 wherein said optical combiner comprises a prism.

8. An apparatus according to claim 1 wherein said optical combiner comprises a polarizing beamsplitter.

9. An apparatus according to claim 1 wherein said optical combiner comprises a wire grid polarizing beamsplitter.

10. An apparatus according to claim 1 further comprising an analyzer prior to said projection lens in the output image path.

11. An apparatus according to claim 1 wherein said optical combiner combines the modulated light from said first spatial light modulator and said second spatial light modulator along a common axis.

12. An apparatus according to claim 1 further comprising a uniformizer for providing said first incident light beam as a uniform field.

13. An apparatus according to claim 12 wherein said uniformizer is from the set consisting of a lenslet array, an integrator bar, an integrating tunnel.

14. An apparatus according to claim 12 wherein said uniformizer adapts the aspect ratio of said first incident light beam to the aspect ratio of said first spatial light modulator.

15. An apparatus according to claim 1 wherein said first spatial light modulator modulates said first incident light beam during the same time interval as said second spatial light modulator modulates said second incident light beam.

16. An apparatus according to claim 1 wherein, during a periodically repeating time interval, only one of first spatial light modulator or second spatial light modulator is modulating.

17. An apparatus according to claim 1 wherein said first modulation system comprises a polarizer for providing said first incident light beam having a predetermined polarization state.

18. An apparatus according to claim 1 wherein said first modulation system comprises a wire grid polarizer for providing said first incident light beam having a predetermined polarization state.

19. An apparatus according to claim 1 wherein said optical combiner is an X-cube.

20. An apparatus for displaying a color image from digital data, the apparatus comprising:

(a) a first light source for providing an s-polarized incident light beam in a repeated sequence comprising a first color, a second color, and a third color;

(b) a second light source for providing a p-polarized incident light beam in a repeated sequence comprising a fourth color, a fifth color, and a sixth color;

(c) a first spatial light modulator for modulating the polarization state of said s-polarized incident light beam to form a first modulated beam;

(d) a second spatial light modulator for modulating the polarization state of said p-polarized incident light beam to form a second modulated beam;

(e) a dichroic combiner for combining said s-polarized and p-polarized incident light beams along a common illumination axis to form an illumination beam;

(f) a polarization beamsplitter for;

(i) directing said s-polarized incident light beam from said illumination beam to said first spatial light modulator for modulation and for directing said first modulated beam from said first spatial light modulator to a projection lens for projection onto a display surface; and

(ii) directing said p-polarized incident light beam from said illumination beam to said second spatial light modulator for modulation and for directing said second modulated beam from said second spatial light modulator to said projection lens for projection onto said display surface.

21. An apparatus for displaying a color image according to claim 20 further comprising a uniformizer for homogenizing said illumination beam.

22. An apparatus for displaying a color image according to claim 20 wherein said first light source is from the group consisting of lasers, LEDs.

23. An apparatus for displaying a color image according to claim 20 wherein said polarizer is a wire-grid polarizer.

24. An apparatus for displaying a color image according to claim 20 wherein said polarizer comprises a prism.

25. An apparatus for displaying a color image according to claim 20 further comprising a uniformizer for homogenizing light from said first light source.

26. An apparatus for displaying a color image according to claim 25 wherein said uniformizer is taken from the group consisting of a lenslet array, an integrator bar, and an integrating tunnel.

27. An apparatus for displaying a color image according to claim 25 wherein said uniformizer adapts the aspect ratio of said s-polarized incident light beam to the aspect ratio of said first spatial light modulator.

28. An apparatus for displaying a color image from digital data, the apparatus comprising:

(a) a first modulation system for providing a first modulated beam, said first modulation system comprising;

(a1) a first spatial light modulator for modulating a first incident light beam in order to form said first modulated beam according to said digital data;

(a2) a first light source for providing a first color beam as said first incident light beam;

(a3) a second light source for providing a second color beam as said first incident light beam;

(b) a second modulation system for providing a second modulated beam, said second modulation system comprising;

(b1) a second spatial light modulator for modulating a second incident light beam in order to form said second modulated beam according to said digital data;

(b2) a third light source for providing a third color beam as said second incident light beam;

(b3) a fourth light source for providing a fourth color beam as said second incident light beam;

(c) a third modulation system for providing a third modulated beam, said third modulation system comprising;

(c1) a third spatial light modulator for modulating a third incident light beam in order to form said third modulated beam according to said digital data;

(c2) a fifth light source for providing a fifth color beam as said third incident light beam;

(c3) a sixth light source for providing a sixth color beam as said third incident light beam; and

(d) an optical combiner for directing said first, second, and third modulated beams toward a lens for projection onto a display surface.

29. An apparatus for displaying a color image according to claim 28 wherein said first modulation system further comprises a polarization beamsplitter for directing polarized light from said first light source to form said first modulated beam.

30. An apparatus for displaying a color image according to claim 29 wherein said polarizer is a wire-grid polarizer.

31. An apparatus for displaying a color image according to claim 28 wherein said first light source is taken from the group consisting of LEDs and lasers.

32. An apparatus for displaying a color image according to claim 28 further comprising a uniformizer for providing said first color beam having a uniform field.

33. An apparatus for displaying a color image according to claim 32 wherein said uniformizer is from the group consisting of lenslet array, integrator bar, integrating tunnel.

34. An apparatus for displaying a color image according to claim 32 wherein said uniformizer adapts the aspect ratio of said first incident light beam to the aspect ratio of said first spatial light modulator.

35. An apparatus for displaying a color image from digital data according to claim 28 wherein the resolutions of said first, second, and third spatial light modulators are not all equal.

36. An apparatus for displaying a color image from digital data, comprising:

(a) a first modulation system for providing a first modulated beam, said first modulation system comprising;

(a1) means for modulating a first incident light beam in order to form said first modulated beam according to said digital data;

(a2) means for providing said first incident light beam in a cyclic sequence wherein a first color beam alternates with a second and third color beam;

(b) a second modulation system for providing a second modulated beam, said second modulation system comprising;

(b1) means for modulating a second incident light beam in order to form said second modulated beam according to said digital data;

(b2) means for providing said second incident light beam in a cyclic sequence wherein a fourth color beam alternates with a fifth and sixth color beam;

(c) means for combining said first and second modulated beams to form a combined, six-color modulated beam; and

(d) means for projecting said combined, six-color modulated beam onto a display surface.

37. An apparatus for displaying a color image from digital data, the apparatus comprising:

(a) a first spatial light modulator for modulating a first incident light beam from a first light source to form a first color modulated beam;

(b) a second spatial light modulator for modulating a second incident light beam from a second light source to form a second color modulated beam;

(c) a third spatial light modulator for modulating a third incident light beam from a third light source to form a third color modulated beam;

(d) a fourth spatial light modulator for modulating a fourth incident light beam from a fourth light source to form a fourth color modulated beam;

(e) a fifth spatial light modulator for modulating a fifth incident light beam from a fifth light source to form a fifth color modulated beam;

(f) a sixth spatial light modulator for modulating a sixth incident light beam from a sixth light source to form a sixth color modulated beam;

(g) means for combining said first, second, third, fourth, fifth, and sixth color modulated beams to form a combined color beam; and

(h) means for projection of said combined color beam onto a display surface.

38. An apparatus for displaying a color image from digital data according to claim 37 further comprising means for uniformizing said first color modulated beam.

39. An apparatus for displaying a color image from digital data according to claim 37 wherein the resolutions of said first, second, third, fourth, fifth, and sixth spatial light modulators are not all equal.

40. An apparatus for displaying a color image from digital data according to claim 37 wherein said first light source is taken from the set consisting of laser, LED.

41. An apparatus for displaying a color image from digital data, the apparatus comprising an OLED capable of simultaneously displaying at least five colors.

42. An apparatus for displaying a color image from digital data comprising:

(a) a first OLED for forming a first multicolor image beam;

(b) a second OLED for forming a second multicolor image beam;

(c) combining means for combining said first and second multicolor image beams to form a full multicolor image beam; and

(d) projection means for projecting said full multicolor image beam onto a display surface.

43. An apparatus for displaying a color image from digital data according to claim 42 wherein said first multicolor image beam comprises a first set of colors and said second multicolor image beam comprises a second set of colors and said first set of colors is not identical to said second set of colors.

44. An apparatus for displaying a color image from digital data comprising:

(a) a first polymer light emitting diode for forming a first multicolor image beam;

(b) a second polymer light emitting diode for forming a second multicolor image beam;

(c) combining means for combining said first and second multicolor image beams to form a full multicolor image beam; and

(d) projection means for projecting said full multicolor image beam onto a display surface.

45. A method for displaying a color image from digital data, the method comprising:

(a) forming a first modulated beam by;

(a1) providing a first color beam from a first light source;

(a2) providing a second color beam from a second light source;

(a3) providing a third color beam from a third light source;

(a4) in a repeated sequence, alternately directing said first, second, and third color beam to a first spatial light modulator as a first incident light beam, said first spatial light modulator modulating said first incident light beam as an array of pixels to form said first modulated beam;

(b) forming a second modulated beam by;

(b1) providing a fourth color beam from a fourth light source;

(b2) providing a fifth color beam from a fifth light source;

(b3) providing a sixth color beam from a sixth light source;

(b4) in a repeated sequence, alternately directing said fourth, fifth, and sixth color beam to a second spatial light modulator as a second incident light beam, said second spatial light modulator modulating said second incident light beam as an array of pixels to form said second modulated beam; and

(c) combining said first modulated beam and said second modulated beam to form an output beam and projecting said output beam onto a surface in order to form the color image.

46. A method for projecting a color image according to claim 45 wherein the transition between directing said first color beam and said second color beam to said first spatial light modulator is substantially simultaneous with the transition between directing said fourth color beam and said fifth color beam to said second spatial light modulator.

47. A method for projecting a color image according to claim 45 wherein said first spatial light modulator is an LCD.

48. A method for expanding color gamut according to claim 45 wherein said first spatial light modulator is a digital micromirror device.

49. A method for expanding color gamut according to claim 45 wherein the step of combining uses a dichroic surface.

50. A method for expanding color gamut according to claim 45 wherein the step of combining uses a dichroic prism.

51. A method for expanding color gamut according to claim 45 wherein the step of combining uses a polarization beamsplitter.

52. A method for displaying a color image from digital data, the method comprising:

(a) forming a first modulated beam by;

(a1) providing a first color beam from a first light source;

(a2) providing a second color beam from a second light source;

(a3) in a repeated sequence, alternately directing said first and said second color beam to a first spatial light modulator as a first incident light beam, said first spatial light modulator modulating said first incident light beam as an array of pixels to form said first modulated beam;

(b) forming a second modulated beam by;

(b1) providing a third color beam from a third light source;

(b2) providing a fourth color beam from a fourth light source;

(b3) in a repeated sequence, alternately directing said third and said fourth color beam to a second spatial light modulator as a second incident light beam, said second spatial light modulator modulating said second incident light beam as an array of pixels to form said second modulated beam;

(c) forming a third modulated beam by;

(c1) providing a fifth color beam from a fifth light source;

(c2) providing a sixth color beam from a sixth light source;

(c3) in a repeated sequence, alternately directing said fifth and said sixth color beam to a third spatial light modulator as a third incident light beam, said third spatial light modulator modulating said third incident light beam as an array of pixels to form said third modulated beam; and

(d) combining said first, second, and third modulated beams to form an output beam and projecting said output beam onto a surface in order to form the color image.

53. A method for displaying a color image according to claim 52 wherein the step of combining uses a dichroic prism.

54. A method for displaying a color image according to claim 52 wherein said first, second, and third modulated beams do not have the same resolution.

55. A method for displaying a color image from digital data, the method comprising:

(a) forming a first modulated beam by modulating a first color beam at a first spatial light modulator;

(b) forming a second modulated beam by modulating a second color beam at a second spatial light modulator;

(c) forming a third modulated beam by modulating a third color beam at a third spatial light modulator;

(d) forming a fourth modulated beam by modulating a fourth color beam at a fourth spatial light modulator;

(e) forming a fifth modulated beam by modulating a fifth color beam at a fifth spatial light modulator;

(f) forming a sixth modulated beam by modulating a sixth color beam at a sixth spatial light modulator; and

(g) combining said first, second, third, fourth, fifth, and sixth modulated beams to form a multicolor beam and projecting said multicolor beam onto a display surface.

56. A method for displaying a color image according to claim 55 wherein said first spatial light modulator differs in resolution from at least one of said second, third, fourth, fifth, and sixth spatial light modulators.

57. A method for minimizing flicker in a digital display system that modulates, in a display sequence, a first, a second, a third, a fourth, a fifth, and a sixth color respectively from a first, a second, a third, a fourth, a fifth, and a sixth color source, the method comprising the steps of:

(a) arranging said first, second, third, fourth, fifth, and sixth colors in a luminance sequence in order of highest, second highest, third highest, fourth highest, fifth highest, and sixth highest relative luminance value;

(b) using said luminance sequence, grouping said first, second, third, fourth, fifth, and sixth colors into first, second, and third pairs, such that each said pair contains one of said first, second, third, fourth, fifth, and sixth colors having highest, second highest, or third highest relative luminance value and one of said first, second, third, fourth, fifth, and sixth colors having fourth highest, fifth highest, or sixth highest relative luminance value; and

(c) sequentially modulating said first, second, third, fourth, fifth, and sixth colors in a sequence of said first, second, and third pairs, thereby smoothing the luminance transition between colors.

58. A method for minimizing flicker in a digital display system according to claim 57 further comprising the step of adjusting luminance for at least one of said first, second, third, fourth, fifth, and sixth colors by adjusting power to the corresponding at least one of said first, second, third, fourth, fifth, and sixth color source.

59. A method for displaying a color image from digital data comprising providing a color OLED capable of emitting at least five colors.

60. A method for displaying a color image from digital data comprising providing a color polymer light emitting diode capable of emitting at least five colors.

61. A method for displaying a color image from digital data comprising:

(a) providing image data for at least a first and a second color to a first OLED and emitting said at least said first and said second color from said first OLED as a first multicolor modulated beam;

(b) providing image data for at least a third and a fourth color to a second OLED and emitting said at least said third and said fourth color from said second OLED as a second multicolor modulated beam;

(c) combining said first and said second multicolor modulated beams to form a combined multicolor modulated beam; and

(d) directing said combined multicolor modulated beam to a display surface.

62. A method for displaying a color image according to claim 61 wherein said fourth color is substantially identical to said second color and wherein the act of combining said first and said second multicolor modulated beams offsets said second multicolor modulated beam from said first multicolor modulated beam, increasing the pixel resolution of said combined multicolor modulated beam thereby.

63. A method for displaying a color image from digital data comprising:

(a) providing image data for at least a first and a second color to a first polymer light emitting diode and emitting said at least said first and said second color from said first polymer light emitting diode as a first multicolor modulated beam;

(b) providing image data for at least a third and a fourth color to a second polymer light emitting diode and emitting said at least said third and said fourth color from said second polymer light emitting diode as a second multicolor modulated beam;

(c) combining said first and said second multicolor modulated beams to form a combined multicolor modulated beam; and

(d) directing said combined multicolor modulated beam to a display surface.