Mirror-based projection system with a programmable control unit for controlling a spatial light modulator

• US 7,498,648 B2
• Filed: 01/12/2006
• Issued: 03/03/2009
• Est. Priority Date: 07/24/2003
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Patel, Satyadev, Richards, Peter, Huibers, Andrew
• Primary Examiner(s): Smoot; Stephen W
• Application Number:
  US11/332,594
• Publication Number:
  US 20060175622A1
• Time in Patent Office: 1,146 Days
• Field of Search: 257/E33.072, 345/31
• US Class Current: 257/436
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: H04N 5/7458 the modulator being an array of deformable mirrors, e.g. digital micromirror device [DMD]

Abstract

A projection system is disclosed herein. The projection system employs a spatial light modulator comprising an array of individually addressable pixels for modulating the incident light based on image data. The modulated light is projected on a screen for viewing.

Claims

1. A projection system, comprising:

an illumination system providing light;

a spatial light modulator comprising an array of reflective and deflectable mirror plates for modulating the light;

a control unit composed of a field-programmable-gate-array for controlling the spatial light modulator in modulating the light, wherein an application-specific-integrated-circuit is absent from the control unit;

a data conversion module designated for converting a set of image data into a set of bitplane data, said module being implemented in the field-programmable-gate-array through a set of configuration data such that the field-programmable-gate-array is capable to output the bitplane data to the spatial light modulator; and

a projection lens for projecting the modulated light; and

screen on which the modulated light is projected.

2. The system of claim 1, wherein the field-programmable-gate-array is a volatile field-programmable-gate-array that is connected to a non-volatile memory wherein a set of configuration data for configuring and initializing the field-programmable-gate-array is stored.

3. The system of claim 2, wherein the memory stored therein the set of configuration data is a flash memory.

4. The system of claim 3, wherein the bitplane data is capable of being directly used by the spatial light modulator for producing the desired image without modification.

5. The system of claim 1, wherein the field-programmable-gate-array is a non-volatile field-programmable-gate-array and stored therein is a set of data for configuring and initializing the field-programmable-gate-array at a time when the field-programmable-gate-array is turned ON or OFF.

6. The system of claim 1, wherein a center-to-center distance between adjacent mirror plates of the array is from 4.38 to 10.16 microns.

7. The system of claim 1, further comprising:

an array of addressing electrodes associated with the mirror plates for electrostatically moving the mirror plates;

an array of memory cells each of which is connected to an addressing electrode for storing a state of the addressing electrodes; and

wherein the memory cells in a row of the memory cell array is connected to first and second wordlines for actuating the memory cells, and wherein the first and second wordlines connect different memory cells of the row.

8. The system of claim 7, wherein each wordline connects every other memory cell in the row of the memory cell array.

9. The system of claim 1, further comprising:

means for directing a light beam modulated by one reflective mirror plate onto different locations on the screen.

10. The system of claim 9, wherein the means comprises a movable folding mirror disposed in a propagation path of the modulated light between the spatial light modulator and screen.

11. The system of claim 9, wherein the means comprises a birefringent crystal with a set of electrodes attached thereto so as to allow electric voltages be applied.

12. The system of claim 1, wherein the illumination system comprises a LED for providing the light.

13. The system of claim 12, wherein the LED is capable of providing white color.

14. The system of claim 1, wherein the illumination system comprises an array of LEDs of different characteristic spectrums.

15. The system of claim 14, wherein the LED array comprises LEDs capable of producing red, green, and blue colors.

16. The system of claim 15, wherein the LEDs of the different colors have different numbers.

17. The system of claim 14, wherein the illumination system further comprises:

a fly-eye lens.

18. The system of claim 14, wherein a color wheel with a set of color segments is absent from the system.

19. The system of claim 1, further comprising:

another spatial light modulator composed of an array of reflective and deflectable mirror plates.

20. The system of claim 19, wherein said another spatial light modulator and said modulator are enclosed within a space between a package lid and a package substrate.

21. The system of claim 1, wherein the illumination system comprises an arc lamp.

22. The system of claim 1, wherein a gap between adjacent reflective mirror plates is from 0.1 to 1 micron.

23. The system of claim 1 being a rear projection system.

24. The system of claim 1 being a front projection TV.

25. A projection system, comprising:

a light-emitting-diode (LED) providing light;

a spatial light modulator comprising an array of micromirror devices, each of which comprises a deflectable and reflective mirror plate associated with an addressing electrode for electrostatically moving the mirror plate;

a control unit composed of a field-programmable-gate-array configured so as to be able to control the spatial light modulator in an operation; and

an optical element for projecting the modulated light on a screen.

26. The system of claim 25, wherein the control unit comprises a data conversion module implemented in the field-programmable-gate-array through a set of configuration data such that a set of image data can be converted into a set of bitplane data by the field-programmable-gate-array.

27. The system of claim 25, wherein the field-programmable-gate-array is volatile;

and wherein the control unit further comprises a memory stored therein a set of configuration data for configuring and initializing the field-programmable-gate-array when it is powered on.

28. The system of claim 25, wherein the field-programmable-gate-array is non-volatile.

29. The system of claim 25 being a rear-projector.

30. The system of claim 25 being a front-projector.

31. The system of claim 25, wherein a center-to-center distance between adjacent micromirror devices in the array is from 4.38 to 10.16 microns.

32. The system of claim 25, wherein a gap between adjacent micromirror devices is from 0.1 to 1 micron.

33. The system of claim 25, wherein an application-specific-integrated-circuit is absent from the control unit.

34. The system of claim 25, further comprising:

an array of addressing electrodes associated with the mirror plates for electrostatically moving the mirror plates;

an array of memory cells each of which is connected to an addressing electrode for storing a state of the addressing electrodes; and

wherein the memory cells in a row of the memory cell array is connected to first and second wordlines for actuating the memory cells, and wherein the first and second wordlines connect different memory cells of the row.

35. The system of claim 25, further comprising:

means for directing a light beam modulated by one reflective mirror plate onto different locations on the screen.

36. The system of claim 25, wherein the LED is capable of providing white color.

37. The system of claim 25, wherein the LED is a member of an array of LEDs of different characteristic spectrums.

38. The system of claim 37, wherein the LED array comprises LEDs capable of producing red, green, and blue colors.

39. The system of claim 25, wherein farther comprising:

a fly-eye lens for directing the light from the LED to the spatial light modulator.

40. A projection system, comprising:

an illumination system providing light;

a reflective spatial light modulator on which light from the light source is incident, the spatial light modulator comprising,

means for modulating pixels of the spatial light modulator such that pixels in an ON state direct light as a first pixel pattern via projection optics onto a target, wherein the intensity vs. distance across a row of projected pixels on the target at a particular time T1, FWHM, defined as the fall width at half maximum of an intensity peak for a particular pixel, is less than 70% of the pitch, wherein the pitch is defined as the distance between adjacent intensity peaks;

a control unit composed of a field-programmable-gate-array implemented therein a plurality of fanctional modules for controlling the illumination system and array of micromirror devices; and

an optical element for projecting the modulated light on a screen.

41. The system of claim 40, wherein the control unit comprises a data conversion module implemented in the field-programmable-gate-array through a set of configuration data such that a set of image data can be converted into a set of bitplane data by the field-programmable-gate-array.

42. The system of claim 40, wherein the field-programmable-gate-array is volatile;

and wherein the control unit further comprises a memory stored therein a set of configuration data for configuring and initializing the field-programmable-gate-array when it is powered on.

43. The system of claim 40, wherein the field-programmable-gate-array is non-volatile.

44. The system of claim 40 being a rear-projector.

45. The system of claim 40 being a front-projector.

46. The system of claim 40, wherein a center-to-center distance between adjacent micromirror devices in the array is from 4.38 to 10.16 microns.

47. The system of claim 40, wherein a gap between adjacent micromirror devices is from 0.1 to 1 micron.

48. The system of claim 40, wherein an application-specific-integrated-circuit is absent from the control unit.

49. The system of claim 40, further comprising:

an array of addressing electrodes associated with the mirror plates for electrostatically moving the mirror plates;

an array of memory cells each of which is connected to an addressing electrode for storing a state of the addressing electrodes; and

wherein the memory cells in a row of the memory cell array is connected to first and second wordlines for actuating the memory cells, and wherein the first and second wordlines connect different memory cells of the row.

50. The system of claim 40, wherein the illumination system comprises a LED that is capable of providing white color.

51. The system of claim 50, wherein the illumination system comprises an array of LEDs of different characteristic spectrums.

52. The system of claim 51, wherein the LED array comprises LEDs capable of producing red, green, and blue colors.

53. A projection system, comprising:

an illumination system capable of producing light;

a spatial light modulator comprising an array of reflective and deflectable mirror plates for modulating the light based on a sequence of bitplane data that is derived from a desired image;

means for converting the desired image to the sequence of bitplane data with a programmed field-programmable-gate-array; and

a screen wherein the modulated light is projected so as to produce the desired image.

54. The system of claim 53, wherein the field-programmable-gate-array is a volatile field-programmable-gate-array that is connected to a non-volatile memory and stored therein is a set of data for configuring and initializing the field-programmable-gate-array.

55. The system of claim 53, wherein the field-programmable-gate-array is a non-volatile field-programmable-gate-array stored therein a set of data for configuring and initializing the field-programmable-gate-array at a time when the field-programmable-gate-array is turned ON or OFF.

56. The system of claim 53 being a front-projector.

57. The system of claim 53 a rear-projection TV.

58. The system of claim 53, wherein an application-specific-integrated-circuit is absent from the field-programmable-gate-array.

59. The system of claim 53, wherein the means comprises a data conversion module implemented in the field-programmable-gate-array through a set of configuration data.

60. A method for displaying a desired image with a spatial light modulator comprising an array of micromirror devices, comprising

directing light to the spatial light modulator;

deriving a sequence of bitplane data from the desired image using a pre-programmed field-programmable-gate-array;

modulating the light by the spatial light modulator according to the sequence of bitplane data; and

projecting the modulated light onto a screen.

61. A projection system, comprising:

an illumination system producing light;

a spatial light modulator optically coupled to the light for modulating the light;

a control unit for controlling the modulation of the spatial light modulator, wherein the control unit comprises a field-programmable-gate-array programmed such that an output of the field-programmable-gate-array comprises a set of bitplane data directly usable by the spatial light modulator for producing an image; and

a screen on which the modulated light is projected so as to form the desired image.