Polarizer apparatus for producing a generally polarized beam of light

• US 6,452,724 B1
• Filed: 06/26/2000
• Issued: 09/17/2002
• Est. Priority Date: 05/14/1998
• Status: Expired due to Term

• Current Assignee: Moxtek (Polatechno Co.,Ltd.)
• Original Assignee: Moxtek (Polatechno Co.,Ltd.)
• Inventors: Hansen, Douglas P., Gunther, John
• Primary Examiner(s): Shafer, Ricky D.
• Application Number:
  US09/603,249
• Time in Patent Office: 813 Days
• Field of Search: 359/352, 359/483, 359/485, 359/486, 359/487, 359/494, 359/495, 359/496, 359/497, 353/20, 362/19
• US Class Current: 359/485.05
• CPC Class Codes: F21V 9/14 for producing polarised light
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G02B 5/3025 Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state G02B5/3008, G02B5/3016 take precedence
• CPC Class Codes: G02B 5/3058 comprising electrically conductive elements, e.g. wire grids, conductive particles

Abstract

A polarizing device has an arrangement of generally parallel elements disposed in an unpolarized source light beam for transmitting polarizations perpendicular to the elements and reflecting polarizations parallel to the elements. The elements may be disposed at substantially any incidence angle and may reflect the reflected beam at substantially any angle. The elements may be disposed on a substrate or embedded in a substrate. The elements may be disposed in a curved layer. The substrate may also have a curved surface. A polarizer apparatus may also have a mirror or the like for redirecting or recapturing the transmitted or reflected beam so they have similar directions or are directed to a common area. The device may also have a wave plate or the like for changing the polarization of the transmitted or reflected beams so they have the same polarization.

Claims

1. A polarizer apparatus for efficiently physically decoupling two orthogonal polarizations of a source light beam within a visible spectrum or near visible spectrum into two generally polarized beams and recapturing at least one of the two beams, the apparatus comprising:

a light source for emitting a source light beam within the visible spectrum or near visible spectrum;

a generally parallel arrangement of thin, elongated elements disposed in the source light beam, the elements having a pitch of less than approximately 0.4 micrometers and providing means for interacting with electromagnetic waves of the source light beam to generally (i) transmit light having a polarization oriented perpendicular to the elements and defining a transmitted beam of a first polarization, and (ii) specularly reflect light having a polarization oriented parallel with the elements and defining a reflected beam of a second polarization; and

a light recapture means separate from the light source and disposed at an orientation in the transmitted beam for intercepting and redirecting substantially all of the transmitted beam so that the transmitted beam is not directed back into the light source;

a polarization reorientation means disposed in at least one of the reflected or transmitted beams for changing the polarization orientation of substantially all of the reflected or transmitted beam so that both the reflected and the transmitted beams have generally the same polarization, thereby substantially converting all the source light beam. to a single polarization.

2. The polarizer apparatus of claim 1, wherein the light recapture means redirects the transmitted beam back to the arrangement of elements.

3. The polarizer apparatus of claim 1, wherein the light recapture means comprises at least two optical elements.

4. The polarizer apparatus of claim 1, wherein the arrangement of elements may be oriented with respect to the source light beam at substantially any incidence angle.

5. The polarizer apparatus of claim 1, wherein the elements are equally spaced.

6. The polarizer apparatus of claim 1, wherein the elements have a pitch of less than approximately 0.13 micrometers.

7. The polarizer apparatus of claim 1, wherein the elements have a width and a pitch, and wherein the ratio of the width to pitch is approximately 40% to 60%.

8. The polarizer apparatus of claim 1, wherein the elements have a length generally greater than approximately 0.7 micrometers.

9. The polarizer apparatus of claim 1, wherein the elements have a pitch and a width generally between 90% to 10% of the pitch.

10. The polarizer apparatus of claim 1, wherein the arrangement of elements is disposed in a generally planer layer.

11. The polarizer apparatus of claim 1, wherein the arrangement of elements is disposed in a generally curved layer.

12. The polarizer apparatus of claim 1, wherein the arrangement of elements is disposed in a generally cylindrical layer.

13. The polarizer apparatus of claim 1, wherein the arrangement of elements is disposed in a generally spherical layer.

14. The polarizer apparatus of claim 1, wherein the arrangement of elements is disposed in a parabolic layer.

15. The polarizer apparatus of claim 1, wherein the arrangement of elements is disposed in an elliptical layer.

16. The polarizer apparatus of claim 1, wherein the arrangement of elements is supported by a substrate.

17. The polarizer apparatus of claim 16, wherein the substrate is a lens.

18. The polarizer apparatus of claim 16, wherein the substrate is a prism.

19. The polarizer apparatus of claim 16, wherein the arrangement of elements is disposed on a first generally planar surface of the substrate, the substrate having a second opposite surface which is generally curved.

20. The polarizer apparatus of claim 16, wherein the arrangement of elements is disposed on a first generally curved surface of the substrate, the substrate having a second opposite surface which is generally curved.

21. The polarizer apparatus of claim 16, wherein the arrangement of elements is disposed on a first surface of the substrate and on a second opposite surface of the substrate.

22. The polarizer apparatus of claim 16, wherein the arrangement of elements is tilted with respect to the source light beam to direct the reflected beam.

23. The polarizer apparatus of claim 1, wherein the light recapture means includes means for redirecting the at least one beam so that both the reflected and transmitted beams are parallel to one another.

24. The polarizer apparatus of claim 23, wherein the reflected and transmitted beams have portions which are substantially collinear.

25. The polarizer apparatus of claim 23, wherein the reflected and transmitted beams have generally the same divergence.

26. The polarizer apparatus of claim 1, further comprising image projection components optically coupled to the polarizer apparatus and operable as an image projection system.

27. The polarizer apparatus of claim 1, further comprising light projection components optically coupled to the polarizer apparatus and operable as a light projection system.

28. The polarizer apparatus of claim 1, further comprising image display components optically coupled to the polarizer apparatus and operable as an image display system.

29. A polarizer apparatus for efficiently physically decoupling two orthogonal polarizations of a source light beam within a visible spectrum or near visible spectrum into two generally polarized beams and recapturing at least one of the two beams, the apparatus comprising:

a light source for emitting a source light beam within the visible spectrum or near visible spectrum;

a generally parallel arrangement of thin, elongated elements disposed in the source light beam, the elements having a pitch, and a width generally between 90% to 10% of the pitch, and providing means for interacting with electromagnetic waves of the source light beam to generally (i) transmit light having a polarization oriented perpendicular to the elements and defining a transmitted beam of a first polarization, and (ii) specularly reflect light having a polarization oriented parallel with the elements and defining a reflected beam of a second polarization; and

a light recapture means separate from the light source and disposed at an orientation in the transmitted beam for intercepting and redirecting substantially all of the transmitted beam so that the transmitted beam is not directed back into the light source;

a polarization reorientation means disposed in at least one of the reflected or transmitted beams for changing the polarization orientation of substantially all of the reflected or transmitted beam so that both the reflected and the transmitted beams have generally the same polarization, thereby substantially converting all the source light beam to a single polarization.

30. The polarizer apparatus of claim 29, wherein the light recapture means redirects the transmitted beam back to the arrangement of elements.

31. The polarizer apparatus of claim 29, wherein the light recapture means comprises at least two optical elements.

32. The polarizer apparatus of claim 29, wherein the arrangement of elements may be oriented with respect to the source light beam at substantially any incidence angle.

33. The polarizer apparatus of claim 29, wherein the elements are equally spaced.

34. The polarizer apparatus of claim 29, wherein the elements have a pitch less than approximately 0.4 micrometers.

35. The polarizer apparatus of claim 29, wherein the elements have a pitch of less than approximately 0.13 micrometers.

36. The polarizer apparatus of claim 29, wherein the elements have a width and a pitch, and wherein the ratio of the width to pitch is approximately 40% to 60%.

37. The polarizer apparatus of claim 29, wherein the elements have a length generally greater than approximately 0.7 micrometers.

38. The polarizer apparatus of claim 29, wherein the arrangement of elements is disposed in a generally planer layer.

39. The polarizer apparatus of claim 29, wherein the arrangement of elements is disposed in a generally curved layer.

40. The polarizer apparatus of claim 29, wherein the arrangement of elements is disposed in a generally cylindrical later.

41. The polarizer apparatus of claim 29, wherein the arrangement of elements is disposed in a generally spherical layer.

42. The polarizer apparatus of claim 29, wherein the arrangement of elements is disposed in a parabolic layer.

43. The polarizer apparatus of claim 29, wherein the arrangement of elements is disposed in an elliptical layer.

44. The polarizer apparatus of claim 29, wherein the arrangement of elements is supported by a substrate.

45. The polarizer apparatus of claim 44, wherein the substrate is a lens.

46. The polarizer apparatus of claim 44, wherein the substrate is a prism.

47. The polarizer apparatus of claim 44, wherein the arrangement of elements is disposed on a first generally planar surface of the substrate, the substrate having a second opposite surface which is generally curved.

48. The polarizer apparatus of claim 44, wherein the arrangement of elements is disposed on a first generally curved surface of the substrate, the substrate having a second opposite surface which is generally curved.

49. The polarizer apparatus of claim 44, wherein the arrangement of elements is disposed on a first surface of the substrate and on a second opposite surface of the substrate.

50. The polarizer apparatus of claim 44, wherein the arrangement of elements is tilted with respect to the source light beam to direct the reflected beam.

51. The polarizer apparatus of claim 29, wherein the light recapture means includes means for redirecting the at least one beam so that both the reflected and transmitted beams are parallel to one another.

52. The polarizer apparatus of claim 51, wherein the reflected and transmitted beams have portions which are substantially collinear.

53. The polarizer apparatus of claim 51, wherein the reflected and transmitted beams have generally the same divergence.

54. The polarizer apparatus of claim 29, further comprising image projection components optically coupled to the polarizer apparatus and operable as an image projection system.

55. The polarizer apparatus of claim 29, further comprising light projection components optically coupled to the polarizer apparatus and operable as a light projection system.

56. The polarizer apparatus of claim 29, further comprising image display components optically coupled to the polarizer apparatus and operable as an image display system.