High-contrast display system with scanned conformal grating device

• US 6,678,085 B2
• Filed: 06/12/2002
• Issued: 01/13/2004
• Est. Priority Date: 06/12/2002
• Status: Expired due to Fees

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Kowarz, Marek W., Phalen, James G.
• Primary Examiner(s): Sugarman, Scott J.
• Assistant Examiner(s): HANIG, RICHARD E
• Application Number:
  US10/171,252
• Publication Number:
  US 20030231373A1
• Time in Patent Office: 580 Days
• Field of Search: 359/291, 359/290, 359/298, 359/227, 359/230, 359/231
• US Class Current: 359/291
• CPC Class Codes: G02B 26/0808 by means of one or more diffracting elements
• CPC Class Codes: H04N 9/3129 scanning a light beam on the display screen scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161

Abstract

An improved projection system that includes a conformal grating electromechanical system (GEMS) device for forming an image on a medium, and also including: a light source providing illumination; a linear array of conformal GEMS devices receiving the illumination; an obstructing element for blocking a zeroth order reflected light beam from reaching the medium; a cross-order filter placed substantially near a Fourier plane of a lens system for blocking a plurality of diffracted cross-order light beams from reaching the medium; a scanning element for moving non-obstructed diffracted light beams relative to the medium; and a controller for providing a data stream to the linear array of conformal GEMS devices.

Claims

1. An improved projection system that includes a conformal grating electromechanical system (GEMS) device for forming an image on a medium, comprising:

a) a light source providing illumination;

b) a linear array of conformal GEMS devices receiving the illumination;

c) an obstructing element for blocking a zeroth order reflected light beam from reaching the medium;

d) a cross-order filter, placed substantially near a Fourier plane of a lens system, for blocking a plurality of diffracted cross-order light beams from reaching the medium;

e) a scanning element for moving non-obstructed diffracted light beams relative to the medium, and

f) a controller for providing a data stream to the linear array of conformal GEMS devices.

2. The improved projection system as claimed in claim 1, wherein the medium is a light reactive printing material.

3. The improved projection system as claimed in claim 1, wherein the medium is a display screen.

4. The improved projection system as claimed in claim 1, wherein the obstructing element is a turning mirror.

5. The improved projection system as claimed in claim 1, wherein the obstructing element is placed between the linear array and a first lens of the lens system.

6. The improved projection system as claimed in claim 1, wherein the obstructing element is placed after a first lens and before a Fourier plane of the lens system.

7. The improved projection system as claimed in claim 1, wherein the scanning element is placed at a Fourier plane of the lens system and the obstructing element is placed between the linear array and the scanning element.

8. The improved projection system as claimed in claim 1, wherein the obstructing element is simultaneously used for delivery of light from the light source to the linear array.

9. The improved projection system as claimed in claim 1, wherein the obstructing element further comprises:

a polarization sensitive beam splitter;

a waveplate; and

a stop to block the zeroth order reflected light beam.

10. The improved projection system as claimed in claim 1, wherein the cross-order filter blocks (+1,+1), (+1,−

1), (−

1,+1) and (−

1,−

1) orders of the diffracted cross-order light beams.

11. The improved projection system as claimed in claim 1, wherein the scanning element is an appropriately-sized scanning mirror so that the diffracted cross-order light beams pass above and below the scanning mirror, thus being functionally equivalent to the cross-order filter.

12. The improved projection system as claimed in claim 1, wherein the obstructing element and the cross-order filter are structurally integrated.

30. The improved projection system as claimed in claim 1, wherein the light source is a laser.

32. The improved projection system as claimed in claim 1, wherein a grating period is oriented perpendicular to a long axis of the linear array.

13. An improved projection system that includes a conformal grating electromechanical system (GEMS) device for forming a multi-color image on a medium, comprising:

a) a plurality of light sources providing illumination;

b) at least one linear array of conformal GEMS devices receiving the illumination;

c) an obstructing element for blocking a zeroth order reflected light beam from reaching the medium;

d) a cross-order filter, placed substantially near a Fourier plane of a lens system, for blocking a plurality of diffracted cross-order light beams from reaching the medium;

e) a scanning element for moving non-obstructed diffracted light beams relative to the medium; and

f) a controller for providing a data stream to at least one linear array of conformal GEMS devices receiving the illumination.

14. The improved projection system as claimed in claim 13, wherein the medium is a light reactive printing material.

15. The improved projection system as claimed in claim 13, wherein the medium is a display screen.

16. The improved projection system as claimed in claim 13, wherein the obstructing element is a turning mirror.

17. The improved projection system as claimed in claim 13, wherein the obstructing element is placed between the linear array and a first lens of the lens system.

18. The improved projection system as claimed in claim 13, wherein the obstructing element is placed after a first lens and before a Fourier plane of the lens system.

19. The improved projection system as claimed in claim 13, wherein the scanning element is placed at a Fourier plane of the lens system and the obstructing element is placed between the linear array and the scanning element.

20. The improved projection system as claimed in claim 13, wherein the obstructing element is simultaneously used for delivery of light from the light source to the linear array.

21. The improved projection system as claimed in claim 13, wherein the obstructing element further comprises:

a polarization sensitive beam splitter;

a waveplate; and

a stop to block the zeroth order reflected light beam.

22. The improved projection system as claimed in claim 13, wherein the cross-order filter blocks (+1,+1), (+1,−

1), (−

1,+1), and (−

1,−

1) orders of the diffracted cross-order light beams.

23. The improved projection system as claimed in claim 13, wherein the scanning element is an appropriately-sized scanning mirror so that the diffracted cross-order light beams pass above and below the scanning mirror, thus being functionally equivalent to the cross-order filter.

24. The improved projection system as claimed in claim 13, wherein the obstructing element and the cross-order filter are structurally integrated.

25. The improved projection system as claimed in claim 13, further comprises at least three light sources of different colors.

26. The improved projection system as claimed in claim 25, wherein the at least three light sources each illuminate a different and respective linear array of conformal GEMS devices.

27. The improved projection system as claimed in claim 26, further comprises a color-combining element.

28. The improved projection system as claimed in claim 27, wherein each different and respective linear array of conformal GEMS devices has its own obstructing element prior to the color-combining element, and a single cross-order filter is placed after the color-combining element.

29. The improved projection system as claimed in claim 27, wherein the obstructing element and the cross-order filter are structurally integrated.

31. The improved projection system as claimed in claim 13, wherein the plurality of light sources are lasers.

33. The improved projection system as claimed in claim 13, wherein a grating period is oriented perpendicular to a long axis of the linear array.