Single-panel field-sequential color display systems

• US 6,707,516 B1
• Filed: 10/02/1998
• Issued: 03/16/2004
• Est. Priority Date: 05/23/1995
• Status: Expired due to Fees

• Current Assignee: RealD Incorporated
• Original Assignee: ColorLink, Incorporated (RealD Incorporated)
• Inventors: Johnson, Kristina M., Sharp, Gary D.
• Primary Examiner(s): Parker, Kenneth
• Application Number:
  US09/165,127
• Time in Patent Office: 1,992 Days
• Field of Search: H04/N.912, H04/N.574, 348/742, 348/743, 348/758, 349/78, 349/79, 349/5, 349/119
• US Class Current: 349/78
• CPC Class Codes: G02B 27/288 Filters employing polarising elements, e.g. Lyot or Solc filters G02B5/3016 takes precedence
• CPC Class Codes: G02F 1/0136 for the control of polarisation, e.g. state of polarisation [SOP] control, polarisation scrambling, TE-TM mode conversion or separation G02F1/0353 takes precedence
• CPC Class Codes: G02F 1/0322 Arrangements comprising two or more independently controlled crystals
• CPC Class Codes: G02F 1/09 based on magneto-optical elements, e.g. exhibiting Faraday effect
• CPC Class Codes: G02F 1/133533 Colour selective polarisers G02F1/1347 takes precedence
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133543 Cholesteric polarisers
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 1/13473 for wavelength filtering or for colour display without the use of colour mosaic filters
• CPC Class Codes: G02F 1/23 for the control of the colour G02F1/03 - G02F1/21 take precedence
• CPC Class Codes: G02F 2413/04 Number of plates greater than or equal to 4
• CPC Class Codes: H04N 5/66 Transforming electric information into light information scanning details H04N3/00
• CPC Class Codes: H04N 5/7441 the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 9/3111 for displaying the colours sequentially, e.g. by using sequentially activated light sources sequential projection in colour photography G03B33/08
• CPC Class Codes: H04N 9/3126 for spatial light modulators in series
• CPC Class Codes: H04N 9/3167 for polarizing the light beam polarizing optical systems per se G02B27/28

Abstract

The present invention provides a single-panel field-sequential full color display systems that are less complex, smaller in size and less costly than prior additive split-path color systems, while exhibiting higher light output, greater flexibility and greater reliability than prior single-panel field-sequential systems. In the first preferred embodiment, the display system includes a “frame buffer” style spatial light modulator, in which a frame buffer pixel circuit is integrated into the spatial light modulator. The display system of the present invention also preferably includes on opto-electronic color sequencer which allows for the electronic control of the transmission of additive primary colors.

Claims

1. A display system, comprising:

an opto-electronic color sequencer that receives input light and that selectively outputs color spectra of the input light, wherein the opto-electronic color sequencer comprises at least one modulator stage, the at least one modulator stage comprising a first retarder stack, a second retarder stack, and a modulator positioned between the first and second retarder stacks; and

a spatial light modulator optically coupled to the opto-electronic color sequencer that selectively and spatially alters light in accordance with image information;

wherein the spatial light modulator is selectively driven with color image information in accordance with color spectra selectively output by the opto-electronic color sequencer.

2. The display system of claim 1, wherein the opto-electronic color sequencer comprises:

a first stage that modulates a first color spectrum in accordance with a first signal;

a second stage that modulates a second color spectrum in accordance with a second signal; and

a third stage that modulates a third color spectrum in accordance with a third signal;

wherein the first, second and third stages arc optically coupled.

3. The display system of claim 2, wherein the first, second and third stages do not include a polarizer.

4. The display system of claim 2, wherein the first and third stages modulate the polarization of the first, second and third color spectra, respectively, in accordance with the first, second and third signals, respectively.

5. The display system of claim 2, wherein the first, second and third stages modulate the transmittance of the first, second and third color spectra, respectively.

6. The display system of claim 2, wherein the transmittance of each of the first, second and third spectra is continuously variable in accordance with the first, second and third signals, respectively.

7. The display system of claim 2, wherein the first, second and third stages each comprise a variable saturation filter adapted to provide more than one color saturation state.

8. The display system of claim 2, wherein the first, second and third stages each comprises a variable luminance filter.

9. The display system of claim 2, wherein each of the first, second and third color spectra comprises one of a red, green and blue spectrum.

10. The display system of claim 2, wherein each of the first, second and third color spectra comprises one of a cyan, magenta and yellow spectrum.

11. The display system of claim 2, wherein each of the first, second and third stages is adapted to modulate its respective color spectrum substantially independently of the other stages.

12. The display system of claim 2, wherein each of the first, second and third stages comprise:

a first retarder stack;

a second retarder stack; and

a modulator between the first and second retarder stacks.

13. The display system of claim 12, wherein the second retarder stack in the first stage and the first retarder stack in the second stage comprise a single retarder stack.

14. The display system of claim 12, wherein the modulator in each stage comprises a liquid crystal modulator.

15. The display system of claim 1, wherein the opto-electronic color sequencer comprises;

a first modulator stage that exhibits at least a first color state in a first modulator mode and a black state in a second modulator mode;

a second modulator stage that exhibits a second color state in the first modulator mode and a black state in the second modulator mode; and

a third modulator stage that exhibits a third color state in the first modulator mode and a black state in the second modulator mode;

wherein the first, second and third modulator stages are optically coupled.

16. The display system of claim 15, wherein the first modulator mode is a stack-altered mode and the second modulator mode is a stack-only mode.

17. The display system of claim 15, wherein the first modulator mode is a stack-only mode and the second modulator mode is a stack-altered mode.

18. The display device of claim 15, wherein each of the first, second and third modulator stages is adapted to exhibit its respective color and black states substantially independently of the other modulator stages.

19. The display device of claim 1, further comprising illumination optics that receive source light and output the input light to the opto-electronic color sequencer.

20. The display de,ice of claim 19, wherein the illumination optics comprise a polarizer.

21. The display device of claim 19, wherein the illumination optics comprise a polarization conversion system.

22. The display device of claim 19, wherein the polarization conversion system comprises:

a polarizing beamsplitter that transmits a first portion of the source light having a first polarization state as a first source light portion and reflects a second portion of the source light having a second polarization state that is orthogonal to the first polarization state as a second source light portion;

a reflector that reflects the second source light portion in a direction that is substantially parallel to a propagation direction of the first source light portion;

a polarization rotator that is positioned to receive the second source light 10 portion before or after the second source light portion is reflected by the reflector, and that rotates the polarization of the second source light portion to the first polarization state; and

a lens that receives and substantially collimates the first and second source light portions that arc polarized in the first polarization state.

23. The display system of claim 22, wherein the reflector comprises a right angle prism.

24. The display system of claim 23, wherein the polarization rotator comprises a retarder attached to one of an input face of the right angle prism, an output face of the right angle prism and an output face of the polarizing beamsplitter.

25. The display system of claim 24, wherein the retarder comprises a half-wave retarder that is substantially achromatic.

26. The display system of claim 22, wherein the tens comprises a condenser lens.

27. The display system of claim 22, further comprising at least one filter that receives the source light and that outputs filtered source light to the polarizing beamsplitter.

28. The display system of claim 27, wherein the at least one filter substantially alters out ultraviolet and/or infrared light from the source light.

29. The display system of claim 22, further comprising an aperture configured and positioned such that substantially all of the source light that passes through the aperture is coupled into the polarizing beamsplitter.

30. The display system of claim 22, further comprising a polarizer that is positioned to receive the first and second source light portions that are polarized in the first polarization state, and that blocks residual light that is not polarized in the fist polarization state.

31. The display device of claim 21, wherein the polarization conversion system comprises:

a first lens array;

a second lens array; and

an array of polarizing beamsplitter units positioned between the first and second lens arrays, wherein each polarizing beamsplitter unit comprises;

a polarizing beamsplitter that transmits a first portion of the source having a first polarization state and reflects a second portion of the source light having a second polarization state that is orthogonal to the first polarization state,

a reflector that reflects the second source light portion in a direction that is substantially parallel to a propagation direction of the first source light portion, and

a polarization rotator that is positioned to receive the second source light portion before or after the second source light portion is reflected by the reflector, and that rotates the polarization of the second source light portion to the first polarization state;

wherein the first lens array focuses the source light into the polarizing beamsplitters, and wherein each lens of the second lens array receives first and second portions of the source light from respective a polarizing beamsplitter unit.

32. The display system of claim 31, wherein the reflector in each polarizing beamsplitter unit comprises a beamsplitter cube.

33. The display device of claim 32, wherein the beamsplitter cube is attached to an output face of the polarizing beamsplitter.

34. The display system of claim 32, wherein the polarization rotator in each polarizing beamsplitter unit comprises a retarder attached to one of an input face of the beamsplitter cube, an output face of the beamsplitter cube and an output face of the polarizing beamsplitter.

35. The display system of claim 36, wherein the retarder comprises a half-wave retarder that is substantially achromatic.

36. The display system of claim 31, further comprising a polarizer that is positioned to receive the first and second source light portions that are polarized in the first polarization state, and that blocks residual light that is not polarized in the first polarization state.

37. The display system of claim 31, further comprising a lens that is positioned to receive the first and second source light portions from the second lens array, wherein the second lens array and the lens together substantially collimate the first and second source light portions.

38. The display system of claim 1, wherein the spatial light modulator comprises a reflective spatial light modulator.

39. The display system of claim 1, wherein the spatial light modulator comprises a transmissive spatial light modulator.

40. The display system of claim 1, wherein the spatial light modulator comprises an analog spatial light modulator.

41. The display system of claim 40, wherein the analog spatial light modulator comprises a nematic liquid crystal spatial light modulator.

42. The display system of claim 1, wherein the spatial light modulator comprises a binary spatial light modulator.

43. The display system of claim 42, wherein the binary spatial light modulator comprises a digital mirror device.

44. The display system of claim 42, wherein the binary spatial light modulator comprises a chiral smectic spatial liquid crystal spatial light modulator.

45. The display system of claim 1, wherein the spatial light modulator comprises an optically addressed spatial light modulator.

46. The display system of claim 1, wherein the opto-electronic color sequencer is adapted to selectively output red green, blue and white spectrum.

47. The display system of claim 1, wherein the opto-electronic color sequencer is adapted to selectively output red, green, blue, yellow, and white spectra.

48. The display system of claim 1, wherein the opto-electronic color sequencer is adapted to selectively output red, green, blue, cyan, magenta and yellow spectra.

49. A display system, comprising:

an opto-electronic color sequencer that receives input light and that selectively outputs color spectra of the input light, wherein the opto-electronic color sequencer comprises at least one modulator stage, the at least one modulator stage comprising a first retarder stack, a second retarder stack, and a modulator positioned between the first and second retarder stacks; and

a frame buffer spatial light modulator optically coupled to the opto-electronic color sequencer that selectively and spatially alters light in accordance with image information;

wherein the frame buffer imager spatial light modulator is selectively driven with color image information in accordance with color spectra selectively output by the opto-electronic color sequencer.

50. The display system of claim 49, wherein the frame buffer spatial light modulator comprises a plurality of pixels, each pixel comprising:

a pixel electrode;

a driving circuit coupled to the pixel electrode to drive the pixel electrode to a present pixel value; and

a holding unit coupled to the driving circuit, and adapted to hold a future pixel value while the hiving circuit drives the pixel electrode with the present pixel value.

51. The display system of claim 49, wherein the frame buffer spatial light modulator comprises a reflective frame buffer spatial light modulator.

52. The display system of claim 49, wherein the frame buffer spatial light modulator comprises a transmissive frame buffer spatial light modulator.

53. The display system of claim 52, further comprising a lens array that focuses light output by the opto-electronic color sequencer through pixels in the transmissive frame buffer spatial light modulator.

54. The display system of claim 49, wherein the frame buffer spatial light modulator comprises an analog frame buffer spatial light modulator.

55. The display system of claim 54, wherein the analog frame buffer spatial light modulator comprises a nematic liquid crystal spatial light modulator.

56. The display system of claim 54, wherein the frame buffer spatial light modulator comprises a binary frame buffer spatial light modulator.

57. The display system of claim 56, wherein the binary frame buffer spatial light modulator comprises a digital mirror device.

58. The display system of claim 56, wherein the binary, frame buffer spatial light modulator comprises a chiral smectic spatial liquid crystal spatial light modulator.

59. The display system of claim 54, wherein the frame buffer spatial light modulator comprises an optically addressed spatial light modulator.

60. The display system of claim 54, wherein the opto-electronic color sequencer comprises;

a first stage that modulates a first color spectrum in accordance with a first signal;

a second stage that modulates a second color spectrum in accordance with a second signal; and

a third stage that modulates a third color spectrum in accordance with a third signal;

wherein the first, second and third stages are optically coupled.

61. The display system of claim 60, wherein each of the first, second and third stages is adapted to modulate its respective color spectrum substantially independently of the other stages.

62. The display system of claim 60, wherein each of the first, second and third stages comprise;

a first retarder stack;

a second retarder stack; and

a modulator between the first and second retarder stacks.

63. The display system of claim 62, wherein the second retarder stack in the first stage and the first retarder stack in the second stage comprise a single retarder stack.

64. The display system of claim 54, wherein the opto-electronic color sequencer comprises:

a first modulator stage that exhibits a first color state in a first modulator mode and a black state in a second modulator mode;

a second modulator stage that exhibits a second color state in the first modulator mode and a black state in the second modulator mode; and

a third modulator stage that exhibits a third color state in the first modulator mode and a black state in the second modulator mode;

wherein the first, second and third modulator stages are optically coupled.

65. The display device of claim 64, wherein each of the first, second and third modulator stages is adapted to exhibit its respective color and black states substantially independently of the other modulator stages.

66. The display system of claim 64, wherein each of the first, second and third modulator stages comprise:

a first retarder stack;

a second retarder stack; and

a modulator between the first and second retarder stacks.

67. The display system of claim 66, wherein the second retarder stack in the first stage and the first retarder stack in the second stage comprise a single retarder stack.

68. A display system comprising:

an opto-electronic color sequencer that receives input light and that selectively outputs color spectra of the input light, wherein the opto-electronic color sequencer comprises at least two stages, without any interposing polarizers, that each modulate a polarization state of a respective color spectrum; and

a spatial light modulator optically coupled to the opto-electronic color sequencer that selectively and spatially alters light in accordance with image information;

wherein the spatial light modulator is selectively driven with color image information in accordance with color spectra selectively Output by the opto-electronic color sequencer.