Miniature image generator including optics arrangement

• US 5,596,451 A
• Filed: 01/30/1995
• Issued: 01/21/1997
• Est. Priority Date: 01/30/1995
• Status: Expired due to Term

• Current Assignee: Citizen Finetech Miyota Company Limited (Citizen Electronics Company Limited), Martin Shenker Optical Design Incorporated
• Original Assignee: Martin Shenker Optical Design Incorporated, Displaytech Inc (Micron Technology, Inc.)
• Inventors: Shenker, Martin, Weissman, Paul E., Handschy, Mark A., Meadows, Michael R.
• Primary Examiner(s): Epps, Georgia Y.
• Assistant Examiner(s): Robbins, Thomas
• Application Number:
  US08/380,081
• Time in Patent Office: 722 Days
• Field of Search: 359/13, 359/630, 359/633, 359/635, 359/639, 359/640
• US Class Current: 359/633
• CPC Class Codes: G02B 2027/0154 with movable elements
• CPC Class Codes: G02B 2027/0156 with optionally usable elements
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00

Abstract

An assembly for producing a visual display includes a light-reflecting type spatial light modulator and an illumination arrangement for providing a particular source of light. The spatial light modulator has a light reflecting surface cooperating with a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of reflected, modulated light. The spatial light modulator also has an arrangement for switching the modulating medium between the different states in a controlled way so as to form the overall pattern. The overall assembly further includes an optics arrangement having a first member defining a light reflecting surface. The optics arrangement also has a second member defining (i) a first external face located in proximity to the illumination arrangement, (ii) a second external face located in proximity to the spatial light modulator, (iii) a third external face located in proximity to the light reflecting surface of the first member, and (iv) a fourth external face. The optics arrangement cooperates with the illumination arrangement and the spatial light modulator such that the spatial light modulator forms the overall pattern of modulated light from light provided by the particular source of light and such that the light reflecting surface of the first member forms a magnified image of the overall pattern which is viewable from within a predetermined area which extends away from the fourth face of the second member.

Claims

1. An assembly for producing a visual display said assembly comprising:

(a) a light reflecting type spatial light modulator including a light reflecting surface cooperating with a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of reflected, modulated light, and means for switching said modulating medium between said different states in a controlled way so as to form said overall pattern;

(b) illumination means for providing a particular source of light; and

(c) optics means including a first member defining a light reflecting surface configured to direct reflected light into a predetermined area and a second member defining a first external face located in proximity to said illumination means, a second external face located in proximity to said spatial light modulator, a third external face located in proximity to the light reflecting surface of said first member, and a fourth external face, said optics means cooperating with said illumination means and said spatial light modulator such that said spatial light modulator forms said overall pattern of light from light provided by said particular source of light and such that the light reflecting surface of said first member directs light provided by the particular source of light from said spatial light modulator into said predetermined area extending outwardly from the fourth face of said second member in a way which allows a magnified image of the overall pattern of light formed at and by said spatial light modulator to be viewed from within said predetermined area, said overall pattern of light serving as said visual display.

2. An assembly according to claim 1 wherein said first member directs light provided by the particular source of light from said spatial light modulator into said predetermined area extending outwardly from the fourth face in a way which forms a real image of said particular source within said predetermined area, whereby the magnified image of the overall pattern of light formed by said spatial light modulator can be viewed, in its entirety, from within said predetermined area.

3. An assembly according to claim 1 wherein said illumination means produces unpolarized light which serves initially as said particular source of light, wherein said spatial light modulator acts on specifically polarized light, and wherein said optics means includes polarizing means, located optically between said illumination means and said predetermined area, for polarizing the particular source of light in ways which allow said spatial light modulator to form said overall pattern of light and which allow the light reflecting surface of said first member to direct the particular source of light from said spatial light modulator into said predetermined area so that the magnified image of the overall pattern of light formed by said spatial light modulator can be viewed, in its entirety, from within said predetermined area.

4. An assembly according to claim 3 wherein said polarizing means includes a polarizer-analyzer which forms part of said second member.

5. An assembly according to claim 4 wherein said second member is a polarizer-analyzer beam splitting cube which defines said first through fourth external faces.

6. An assembly according to claim 5 wherein said polarizing means includes a prepolarizer positioned optically between said illumination source and the first external face of said cube.

7. An assembly according to claim 5 wherein said polarizing means includes a quarter-wave plate positioned optically between the light reflecting surface of said first member and the third external face of said cube.

8. An assembly according to claim 7 wherein the light modulating medium of said spatial light modulator is ferroelectric liquid crystal material and wherein the switching means of said spatial light modulator includes active matrix circuitry.

9. An assembly according to claim 3 wherein said polarizing means includes a prepolarizer positioned optically between said illumination source and the first external face of said second member.

10. An assembly according to claim 3 wherein said polarizing means includes a quarter-wave plate positioned optically between the light reflecting surface of said first member and the third external face of said second member.

11. An assembly according to claim 3 wherein said second member is a beam splitting cube which defines said first through fourth external faces and which does not include polarizing-analyzing capabilities and wherein said polarizing means includes a polarizer positioned optically between said illumination source and the first external face of said cube and an analyzer positioned optically between said predetermined area and the fourth external face of said cube.

12. An assembly according to claim 11 wherein said polarizing means includes a quarter-wave plate positioned optically between the light reflecting surface of said first member and the third external face of said cube.

13. An assembly for producing a visual display, said assembly comprising:

(a) a light reflecting type spatial light modulator including a light reflecting surface cooperating with a layer of liquid crystal material serving as a light modulating medium switchable between different states so as to act on particularly polarized light in ways which form an overall pattern of modulated light, and means including active matrix circuitry for switching said modulating medium between said different states in a controlled way so as to form said overall pattern;

(b) illumination means for providing a particular source of unpolarized light; and

(c) optics means including (i) means defining a light reflecting surface configured to direct reflected light into a predetermined area, (ii) a polarizer-analyzer beam splitting cube defining a first external face located in proximity to said illumination means, a second external face located in proximity to said spatial light modulator, a third external face located in proximity to the light reflecting surface, and a fourth external face, (iii) a prepolarizer positioned optically between said illumination source and the first external face of said cube, and (iv) a quarter-wave plate positioned optically between the light reflecting surface of said light reflecting surface and the third external face of said cube, said optics means cooperating with said illumination means and said spatial light modulator such that said spatial light modulator forms said overall pattern of light from light provided by said particular source of light and such that said means defining a light reflecting surface directs light provided by the particular source of light from said spatial light modulator into said predetermined area extending outwardly from the fourth face of said second member in a way which allows a magnified image of the overall pattern of light formed at and by said spatial light modulator to be viewed from within said predetermined area while at the same time producing a real image of said source of light within said predetermined area, said overall pattern of light serving as said visual display.

14. An assembly according to claim 13 wherein said spatial light modulator is of the reflective type including a light reflecting surface.

15. An assembly according to claim 14 wherein said polarizer-analyzer beam splitting cube includes an internal polarizing-analyzing film within the cube such that said first and fourth external faces of the cube lie on one side of and confront said polarizing-analyzing film and said second and third faces of the cube lie on the opposite side of and confront said polarizing-analyzing film.

16. An assembly according to claim 14 wherein said polarizer-analyzer beam splitting cube includes an internal polarizing-analyzing film within the cube such that said first and second faces of the cube lie on one side of and confront said polarizing-analyzing film and said third and fourth faces of the cube lie on the opposite side of and confront said polarizing-analyzing film.

17. An assembly for producing a visual display, said assembly comprising:

(a) a light reflecting type of spatial light modulator including a light reflecting surface cooperating with a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of reflected, modulated light, and means for switching said modulating medium between said different states in a controlled way so as to form said overall pattern;

(b) illumination means for providing a particular source of light; and

(c) optics means including (i) a first member defining a light reflecting surface configured to direct reflected light into a predetermined area, (ii) a second member defining a first external face located in proximity to said illumination means, a second external face located in proximity to said spatial light modulator, and a third external face, and (iii) a third member defining a first external face immediately adjacent the third face of said second member, a second external face located in proximity to the light reflecting surface of said first member, and a third external face, said optics means cooperating with said illumination means and said spatial light modulator such that said spatial light modulator forms said overall pattern of light from light provided by said particular source of light and such that the light reflecting surface of said first member directs light provided by the particular source of light from said spatial light modulator into said predetermined area extending outwardly from the third face of said third member in a way which allows a magnified image of the overall pattern of light formed at and by said spatial light modulator to be viewed from within said predetermined area, said overall pattern of light serving as said visual display.

18. An assembly according to claim 17 wherein said third member is a polarizer-analyzer beam splitting cube.

19. An assembly according to claim 18 wherein said second member is a polarizer-analyzer beam splitting cube.

20. An assembly according to claim 17 wherein said first member directs light provided by the particular source of light from said spatial light modulator into said predetermined area extending outwardly from the third face of said third member in a way which forms a real image of said particular source of light within said predetermined area and such that said magnified image of the overall pattern of light formed by said spatial light modulator can be viewed, in its entirety, from within said predetermined area.

21. An assembly according to claim 17 wherein said illumination means produces unpolarized light which serves initially as said particular source of light, wherein said spatial light modulator acts on specifically polarized light and wherein said optics means includes means located optically between said illumination means and said spatial light modulator for polarizing the particular source of light in ways which allow said spatial light modulator to form said overall pattern of light and which allow the light reflecting surface of said first member to direct light provided by the particular source of light from said spatial light modulator into the predetermined area so that a magnified image of the overall pattern of light formed by said spatial light modulator can be viewed, in its entirety, from within said predetermined area.

22. An assembly according to claim 21 wherein said polarizing means includes a polarizer-analyzer which forms part of each of said second and third members.

23. An assembly according to claim 22 wherein each of said second and third members is a polarizer-analyzer beam splitting cube which defines its respective external faces, said second member cube including an internal polarizing-analyzing film within the cube such that its first and second faces lie on one side of and confront said polarizing-analyzing film and its third face and a fourth face of the cube lie on the opposite side of and confront said polarizing-analyzing film, and said third member cube including an internal polarizing-analyzing film within the cube such that its first face and a fourth face of the cube lie on one side of and confront said polarizing-analyzing film and its second and third faces lie on the opposite side of and confront said polarizing-analyzing film.

24. An assembly according to claim 23 wherein said polarizing means includes a quarter-wave plate positioned optically between the light reflecting surface of said first member and the second external face of third member.

25. An assembly according to claim 24 wherein the light modulating medium of said spatial light modulator is ferroelectric liquid crystal material and wherein the switching means of said spatial light modulator includes active matrix circuitry.

26. An assembly according to claim 22 wherein each of said second and third members is a polarizer-analyzer beam splitting cube which defines its respective external faces, said second member cube including an internal polarizing-analyzing film within the cube such that its fast face and a fourth face lie on one side of and confront said polarizing-analyzing film and its second and third faces lie on the opposite side of and confront said polarizing-analyzing film, and said third member cube including an internal polarizing-analyzing film within the cube such that its first face and a fourth face of the cube lie on one side of and confront said polarizing-analyzing film and its second and third faces lie on the opposite side of and confront said polarizing-analyzing film.

27. An assembly according to claim 26 wherein said polarizing means includes a half-wave plate positioned optically between the third face of said second member cube and the fast face of said third member cube.

28. An assembly for producing a visual display, said assembly comprising:

(a) a light reflecting type spatial light modulator including a light reflecting surface cooperating with a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of reflected, modulated light, and means for switching said modulating medium between said different states in a controlled way so as to form said overall pattern;

(b) illumination means for providing at least one particular source of light; and

(c) optics means including (i) a first member defining a light reflecting surface configured to direct reflected light into a predetermined area, (ii) a second member including at least two adjacently positioned submembers at least one submember of which defines a first external face located in proximity to a corresponding one of said particular sources of light and all of the submembers of which together define a second external face located in proximity to said spatial light modulator and a third external face, and (iii) a third member defining a first external face immediately adjacent the third face of the submembers of said second member, a second external face located in proximity to the light reflecting surface of said first member, and a third external face, said optics means cooperating with said illumination means and said spatial light modulator such that said spatial light modulator forms said overall pattern of light from light provided by said particular sources of light and such that the light reflecting surface of said first member directs light provided by the particular sources of light from said spatial light modulator into said predetermined area extending outwardly from the third face of said third member in a way which allows a magnified image of the overall pattern of light formed at and by said spatial light modulator to be viewed from within said predetermined area, said overall pattern of light serving as said visual display.

29. An assembly according to claim 28 wherein said optics means further includes a half wave plate positioned between a first one of said submembers and a second one of said submembers.

30. An assembly according to claim 28 wherein each of said submembers defines a first external face located in proximity to a corresponding one of said particular sources of light.

31. An assembly according to claim 28 wherein each of the submembers of said second member is a polarizer-analyzer beam splitting cube.

32. An assembly according to claim 31 wherein each of the submember cubes of said second member includes an internal polarizing-analyzing film within the cube such that the first and the second faces of said submember cubes lie on one side of and confront said polarizing-analyzing film and the third faces of said submember cubes lie on the opposite side of and confronts said polarizing-analyzing film.

33. An assembly according to claim 32 wherein said third member is a polarizer-analyzer beam splitting cube.

34. An assembly according to claim 33 wherein said third member cube includes an internal polarizing-analyzing film within the cube such that its first face lies on one side of and confronts its polarizing-analyzing film and its second and third faces lie on the opposite side of and confront its polarizing-analyzing film.

35. An assembly for producing a visual display, said assembly comprising:

(a) a spatial light modulator including a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of modulated light, and means for switching said modulating medium between said different states in a controlled way so as to form said overall pattern;

(b) illumination means for providing a particular source of light; and

(c) optics means including at least two polarizer-analyzer beam splitting cubes positioned immediately adjacent one another and immediately adjacent said illumination means and said spatial light modulator in a predetermined manner, said optics means cooperating with said illumination means and said spatial light modulator such that said spatial light modulator forms said overall pattern of light from light provided by said particular source of light and such that the optics means directs light provided by the particular source of light from said spatial light modulator into a predetermined area extending outwardly from one of the cubes in a way which allows a magnified image of the overall pattern of light formed at and by said spatial light modulator to be viewed from within said predetermined area, said overall pattern of light serving as said visual display.

36. An assembly according to claim 35 wherein said optics means includes at least three of said cubes.

37. An assembly according to claim 35 wherein said spatial light modulator is of the light reflecting type.

38. An assembly for producing a visual display, said assembly comprising:

(a) a reflective type spatial light modulator including a light reflecting surface cooperating with a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of reflected, modulated light, and means for switching said modulating medium between said different states in a controlled way so as to form said overall pattern;

(b) a light arrangement including removably replaceable illumination means for providing a particular source of light; and

(c) optics means including means defining a light reflecting surface configured to direct reflected light into a predetermined area and a polarizer-analyzer beam splitting cube having one face thereof attached to said light arrangement in a way which allows said illumination means to be removed and replaced, a second face thereof attached to said spatial light modulator, a third face thereof attached to said means defining said light reflecting surface in a way which allows said light reflecting surface to be adjustably moved to a limited extent towards and away from said third face, and a fourth face, said optics means cooperating with said light arrangement and said spatial light modulator such that said spatial light modulator forms said overall pattern of light from light provided by said particular source of light and such that said light reflecting surface directs light provided by the particular source of light from said spatial light modulator into said predetermined area extending outwardly from the fourth face of said cube in a way which allows a magnified image of the overall pattern of light formed at and by said spatial light modulator to be viewed, from within said predetermined area, said overall pattern of light serving as said visual display.

39. An assembly for producing a visual display, said assembly comprising:

(a) a spatial light modulator including a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of modulated light, and means for switching said modulating medium between said different states in a controlled way so as to form said overall pattern;

(b) illumination means for providing a particular source of light; and

(c) optics means including a first member defining a light reflecting surface configured to direct reflected light into a predetermined area and a second member defining a first external face located in proximity to said spatial light modulator, a second external face located in proximity to the light reflecting surface of said first member, and a third external face, said optics means cooperating with said illumination means and said spatial light modulator such that said spatial light modulator forms said overall pattern of light from light provided by said particular source of light and such that the light reflecting surface of said first member directs light provided by the particular source of light from said spatial light modulator into said predetermined area extending outwardly from the third face of said second member in a way which allows a magnified image of the overall pattern of light formed at and by said spatial light modulator to be viewed from within said predetermined area, said overall pattern of light serving as said visual display.

40. An assembly according to claim 39 wherein said second member is a polarizer-analyzer beam splitting cube which defines said first through third external faces.

41. An assembly according to claim 39 wherein said spatial light modulator is of the light reflecting type.

42. An assembly according to claim 41 wherein said illumination means is transparent and wherein said illumination means is positioned between said spatial light modulator and said first external face of said second member.

43. An assembly for producing a visual display, said assembly comprising:

(a) a reflective type spatial light modulator including a light reflecting surface cooperating with a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of reflected, modulated light, and means for switching said modulating medium between said different states in a controlled way so as to form said overall pattern;

(b) a light arrangement including removably replaceable illumination means for providing a particular source of light; and

(c) optics means including means defining a light reflecting surface configured to direct reflected light into a predetermined area and a polarizer-analyzer beam splitting cube having one face thereof attached to said light arrangement in a way which allows said illumination means to be removed and replaced, a second face thereof attached to said spatial light modulator in a way which allows said spatial light modulator to be adjustably moved to a limited extent towards and away from said second face, a third face thereof attached to said means defining said light reflecting surface, and a fourth face, said optics means cooperating with said light arrangement and said spatial light modulator such that said spatial light modulator forms said overall pattern of light from light provided by said particular source of light and such that said light reflecting surface directs light provided by the particular source of light from said spatial light modulator into said predetermined area extending outwardly from the fourth face of said cube in a way which allows a magnified image of the overall pattern of light formed at and by said spatial light modulator to be viewed, from within said predetermined area, said overall pattern of light serving as said visual display.