Optical system for display panel

• US 6,457,834 B1
• Filed: 01/24/2001
• Issued: 10/01/2002
• Est. Priority Date: 01/24/2001
• Status: Expired due to Fees

• Current Assignee: SCRAM Technologies, Inc
• Original Assignee: SCRAM Technologies, Inc
• Inventors: Shoup, Milton J. III, Cotton, Christopher T., Veligdan, James T.
• Primary Examiner(s): Mahoney, Christopher
• Assistant Examiner(s): Cruz, Magda
• Application Number:
  US09/768,639
• Publication Number:
  US 20020140912A1
• Time in Patent Office: 615 Days
• Field of Search: 385/901, 353/69, 353/70, 353/98, 353/122
• US Class Current: 353/122
• CPC Class Codes: G02B 27/0025 for optical correction, e.g. distorsion, aberration
• CPC Class Codes: Y10S 385/901 Illuminating or display apparatus

Abstract

An optical system for producing an accurate image on an optical panel inlet face surface which is highly tilted relative to the image path. The optical system comprises an image source and an imaging element that creates an image from the image source. The optical system also comprises an anamorphic telescope for reducing anamorphic distortion of the image, and a final element for directing the image toward the optical panel. The anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction. The anamorphic telescope includes a first lens group, a second lens group, and a third lens group. The first lens group and the second lens group form a first anamorphic telescopic system, and the second lens group and the third lens group form a second anamorphic telescopic system.

Claims

1. An optical system for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, comprising;

an image source;

an imaging element for creating an image from the image source;

an anamorphic telescope for reducing anamorphic distortion of the image, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction; and

a final element for directing the image toward the display image plane.

2. The optical system of claim 1, wherein the imaging element enlarges magnification of the image equally in the first direction and in the second direction.

3. The optical system of claim 1, wherein the imaging element comprises at least one rotationally symmetric surface.

4. The optical system of claim 1, wherein the imaging element includes at least one lens which is comprised of a low color dispersion material, and at least one additional lens which is comprised of a high color dispersion material such that chromatic aberration of the image is corrected.

5. The optical system of claim 4, wherein the low color dispersion material is acrylic.

6. The optical system of claim 4, wherein the low color dispersion material is Zeonex®

.

7. The optical system of claim 4, wherein the high color dispersion material is polystyrene.

8. The optical system of claim 1, wherein the imaging element comprises at least one lens which is tilted and decentered with respect to a central longitudinal axis of the image source.

9. The optical system of claim 1, wherein the final element is a mirror.

10. The optical system of claim 9, wherein the final element comprises a biconic surface which is both anamorphic and conic in the first direction and in the second direction.

11. The optical system of claim 1, wherein principal light rays between the final element and the display image plane are non-parallel with respect to each other.

12. The optical system of claim 11, wherein the final element has positive power.

13. The optical system of claim 1, wherein the image source is a chromatic image-combining projector.

14. The optical system of claim 1, wherein a center of curvature of the imaging element, anamorphic telescope, and final element are each aligned within a common plane.

15. The optical system of claim 1, wherein the image source, the imaging element, the anamorphic telescope, and the final element each effect a tilt on the image.

16. The optical system of claim 1, wherein one or more elements selected from the group consisting of the image source, the imaging element, the anamorphic telescope, and the final element effect a tilt on the image.

17. The optical system of claim 1, wherein lenses within the imaging element are each aligned along a central longitudinal optical axis, and wherein at least one lens within the anamorphic telescope is tilted and de-centered with respect to the central longitudinal optical axis.

18. The optical system of claim 1, wherein the anamorphic telescope comprises at least one surface of the type selected from the group consisting of spherical, aspherical, diffractive, and Fresnel surfaces.

19. The optical system of claim 1, wherein lenses within the imaging element are each aligned along a central longitudinal optical axis, and wherein the anamorphic telescope comprises spherical and aspherical surfaces, and wherein at least one lens within the anamorphic telescope is tilted and de-centered with respect to the central longitudinal optical axis.

20. The optical system of claim 1, wherein the final element comprises a Fresnel surface.

21. The optical system of claim 1, wherein the display image plane is defined by end portions of a plurality of optical waveguides.

22. The optical system of claim 1, wherein the incident angle θ

is in the range of approximately 50°

-85°

.

23. The optical system of claim 22, wherein the incident angle θ

is approximately 78°

.

24. An optical system for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, comprising;

an image source;

an imaging element for creating an image from the image source;

an anamorphic telescope for reducing anamorphic distortion of the image, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction, wherein the anamorphic telescope includes a first lens group, a second lens group, and a third lens group, wherein the first lens group and the second lens group form a first anamorphic telescopic system, and wherein the second lens group and the third lens group form a second anamorphic telescopic system; and

a final element for directing the image toward the display image plane.

25. The optical system of claim 24, wherein the first anamorphic telescopic system reduces magnification of the image in the first direction.

26. The optical system of claim 25, wherein the second anamorphic telescopic system enlarges magnification of the image in the second direction.

27. The optical system of claim 24, wherein the second anamorphic telescopic system enlarges magnification of the image in the second direction.

28. The optical system of claim 24, wherein the second anamorphic telescopic system reduces magnification of the image in the first direction.

29. The optical system of claim 28, wherein the first anamorphic telescopic system enlarges magnification of the image in the second direction.

30. The optical system of claim 24, wherein the first anamorphic telescopic system enlarges magnification of the image in the second direction.

31. The optical system of claim 24, wherein the first lens group produces negative power in the first direction and positive power in the second direction.

32. The optical system of claim 31, wherein the second lens group produces positive power in the first direction and positive power in the second direction.

33. The optical system of claim 32, wherein the third lens group produces positive power in the first direction and negative power in the second direction.

34. The optical system of claim 24, wherein the first lens group comprises two off-axis rotationally symmetric surfaces and two conic cylindrical surfaces.

35. The optical system of claim 24, wherein the first lens group includes at least one lens which is comprised of a low color dispersion material, and at least one additional lens which is comprised of a high color dispersion material such that chromatic aberration of the image is corrected.

36. The optical system of claim 35, wherein the low color dispersion material is acrylic.

37. The optical system of claim 35, wherein the low color dispersion material is Zeonex®

.

38. The optical system of claim 35, wherein the high color dispersion material is polystyrene.

39. The optical system of claim 24, wherein the second lens group comprises two off-axis rotationally symmetric surfaces and two conic cylindrical surfaces.

40. The optical system of claim 24, wherein the second lens group includes at least one lens which is comprised of a low color dispersion material, and at least one additional lens which is comprised of a high color dispersion material such that chromatic aberration of the image is corrected.

41. The optical system of claim 40, wherein the low color dispersion material is acrylic.

42. The optical system of claim 40, wherein the low color dispersion material is Zeonex®

.

43. The optical system of claim 40, wherein the high color dispersion material is polystyrene.

44. The optical system of claim 24, wherein the third lens group comprises one off-axis rotationally symmetric surface and five conic cylindrical surfaces.

45. The optical system of claim 24, wherein the third lens group includes at least one lens which is comprised of a low color dispersion material, and at least one additional lens which is comprised of a high color dispersion material such that chromatic aberration of the image is corrected.

46. The optical system of claim 45, wherein the low color dispersion material is acrylic.

47. The optical system of claim 45, wherein the low color dispersion material is Zeonex®

.

48. The optical system of claim 45, wherein the high color dispersion material is polystyrene.

49. The optical system of claim 24, wherein the anamorphic telescope performs correction of keystone distortion, and wherein the correction of keystone distortion within the anamorphic telescope is performed primarily by the first lens group with additional correction performed by at least one of the lenses comprising the imaging element, second lens group, and third lens group.

50. The optical system of claim 24, wherein a folding mirror is positioned between the first lens group and the second lens group.

51. The optical system of claim 24, wherein a folding mirror is positioned between the second lens group and the third lens group.

52. The optical system of claim 24, wherein a first folding mirror is positioned between the first lens group and the second lens group, and a second folding mirror is positioned between the second lens group and the third lens group.

53. The optical system of claim 24, wherein each lens group within the anamorphic telescope effects a tilt on the image.

54. A display system having an optical panel and at least one optical system for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, said display system comprising;

an optical panel, comprising;

a plurality of stacked optical waveguides, each having a first end and a second end, wherein an outlet face is defined by the plurality of first ends, and wherein an inlet face is defined by the plurality of second ends; and

at least one coupler provided at the inlet face which redirects light traveling from an axis non-perpendicular to the inlet face to an axis perpendicular to the inlet face;

at least one optical system, each said optical system comprising;

an image source;

an imaging element for creating an image from the image source;

an anamorphic telescope for reducing anamorphic distortion of the image, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction; and

a final element for directing the image toward the display image plane.

55. The display system of claim 54, wherein the imaging element enlarges magnification of the image equally in the first direction and in the second direction.

56. The display system of claim 54, wherein the imaging element comprises at least one rotationally symmetric surface.

57. The display system of claim 54, wherein the imaging element includes at least one lens which is comprised of a low color dispersion material, and at least one additional lens which is comprised of a high color dispersion material such that chromatic aberration of the image is corrected.

58. The display system of claim 57, wherein the low color dispersion material is acrylic.

59. The display system of claim 57, wherein the low color dispersion material is Zeonex®

.

60. The display system of claim 57, wherein the high color dispersion material is polystyrene.

61. The display system of claim 54, wherein the imaging element comprises at least one lens which is tilted and decentered with respect to a central longitudinal axis of the image source.

62. The display system of claim 54, wherein the final element is a mirror.

63. The display system of claim 62, wherein the final element comprises a biconic surface which is both anamorphic and conic in the first direction and in the second direction.

64. The display system of claim 54, wherein principal light rays between the final element and the display image plane are non-parallel with respect to each other.

65. The display system of claim 64, wherein the final element has positive power.

66. The display system of claim 54, wherein the image source is a chromatic image-combining projector.

67. The display system of claim 54, wherein a center of curvature of the imaging element, anamorphic telescope, and final element are each aligned within a common plane.

68. The display system of claim 54, wherein the image source, the imaging element, the anamorphic telescope, and the final element each effect a tilt on the image.

69. The display system of claim 54, wherein one or more elements selected from the group consisting of the image source, the imaging element, the anamorphic telescope, and the final element effect a tilt on the image.

70. The display system of claim 54, wherein lenses within the imaging element are each aligned along a central longitudinal optical axis, and wherein at least one lens within the anamorphic telescope is tilted and de-centered with respect to the central longitudinal optical axis.

71. The display system of claim 54, wherein the anamorphic telescope comprises at least one surface of the type selected from the group consisting of spherical, aspherical, diffractive, and Fresnel surfaces.

72. The display system of claim 54, wherein lenses within the imaging element are each aligned along a central longitudinal optical axis, and wherein the anamorphic telescope comprises spherical and aspherical surfaces, and wherein at least one lens within the anamorphic telescope is tilted and de-centered with respect to the central longitudinal optical axis.

73. The display system of claim 54, wherein the final element comprises a Fresnel surface.

74. The display system of claim 54, wherein the display image plane is defined by the plurality of first ends of the plurality of waveguides.

75. The display system of claim 54, wherein the incident angle θ

is in the range of approximately 50°

-85°

.

76. The display system of claim 75, wherein the incident angle θ

is approximately 78°

.

77. The display system of claim 54, wherein the display system comprises two or more optical systems.

78. The display system of claim 54, wherein the display system comprises three optical systems, wherein the optical systems project red, green and blue light, respectively.

79. The display system of claim 54, wherein each of the plurality of waveguides are formed as flat ribbons extending continuously in a horizontal direction along the outlet face.

80. A display system having an optical panel and at least one optical system for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, said display system comprising;

an optical panel, comprising;

a plurality of stacked optical waveguides, each having a first end and a second end, wherein an outlet face is defined by the plurality of first ends, and wherein an inlet face is defined by the plurality of second ends; and

at least one coupler provided at the inlet face which redirects light traveling from an axis non-perpendicular to the inlet face to an axis perpendicular to the inlet face;

at least one optical system, each said optical system comprising;

an image source;

an imaging element for creating an image from the image source;

an anamorphic telescope for reducing anamorphic distortion of the image, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction, wherein the anamorphic telescope includes a first lens group, a second lens group, and a third lens group, wherein the first lens group and the second lens group form a first anamorphic telescopic system, and wherein the second lens group and the third lens group form a second anamorphic telescopic system; and

a final element for directing the image toward the display image plane.

81. The display system of claim 80, wherein the first anamorphic telescopic system reduces magnification of the image in the first direction.

82. The display system of claim 81, wherein the second anamorphic telescopic system enlarges magnification of the image in the second direction.

83. The display system of claim 80, wherein the second anamorphic telescopic system enlarges magnification of the image in the second direction.

84. The display system of claim 80, wherein the second anamorphic telescopic system reduces magnification of the image in the first direction.

85. The display system of claim 84, wherein the first anamorphic telescopic system enlarges magnification of the image in the second direction.

86. The display system of claim 80, wherein the first anamorphic telescopic system enlarges magnification of the image in the second direction.

87. The display system of claim 80, wherein the first lens group produces negative power in the first direction and positive power in the second direction.

88. The display system of claim 87, wherein the second lens group produces positive power in the first direction and positive power in the second direction.

89. The display system of claim 88, wherein the third lens group produces positive power in the first direction and negative power in the second direction.

90. The display system of claim 80, wherein the first lens group comprises two off-axis rotationally symmetric surfaces and two conic cylindrical surfaces.

91. The display system of claim 80, wherein the first lens group includes at least one lens which is comprised of a low color dispersion material, and at least one additional lens which is comprised of a high color dispersion material such that chromatic aberration of the image is corrected.

92. The display system of claim 91, wherein the low color dispersion material is acrylic.

93. The display system of claim 91, wherein the low color dispersion material is Zeonex®

.

94. The display system of claim 91, wherein the high color dispersion material is polystyrene.

95. The display system of claim 80, wherein the second lens group comprises two off-axis rotationally symmetric surfaces and two conic cylindrical surfaces.

96. The display system of claim 80, wherein the second lens group includes at least one lens which is comprised of a low color dispersion material, and at least one additional lens which is comprised of a high color dispersion material such that chromatic aberration of the image is corrected.

97. The display system of claim 96, wherein the low color dispersion material is acrylic.

98. The display system of claim 96, wherein the low color dispersion material is Zeonex®

.

99. The display system of claim 96, wherein the high color dispersion material is polystyrene.

100. The display system of claim 80, wherein the third lens group comprises one off-axis rotationally symmetric surface and five conic cylindrical surfaces.

101. The display system of claim 80, wherein the third lens group includes at least one lens which is comprised of a low color dispersion material, and at least one additional lens which is comprised of a high color dispersion material such that chromatic aberration of the image is corrected.

102. The display system of claim 101, wherein the low color dispersion material is acrylic.

103. The display system of claim 101, wherein the low color dispersion material is Zeonex®

.

104. The display system of claim 101, wherein the high color dispersion material is polystyrene.

105. The display system of claim 80, wherein the anamorphic telescope performs correction of keystone distortion, and wherein the correction of keystone distortion within the anamorphic telescope is performed primarily by the first lens group with additional correction performed by at least one of the lenses comprising the imaging element, second lens group, and third lens group.

106. The display system of claim 80, wherein a folding mirror is positioned between the first lens group and the second lens group.

107. The display system of claim 80, wherein a folding mirror is positioned between the second lens group and the third lens group.

108. The display system of claim 80, wherein a first folding mirror is positioned between the first lens group and the second lens group, and a second folding mirror is positioned between the second lens group and the third lens group.

109. The display system of claim 80, wherein each group within the anamorphic telescope effects a tilt on the image.

110. A method for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, said method comprising the steps of;

projecting an image from an image source;

creating an image from the projected image with an imaging element;

reducing anamorphic distortion of the image with an anamorphic element, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction; and

directing the image toward the display image plane with a final element.

111. A method for displaying an image onto a display image plane of an optical panel at an incident angle θ

which is greater than zero, said method comprising the steps of;

projecting an image from an image source;

creating an image from the projected image with an imaging element;

reducing anamorphic distortion of the image with an anamorphic element, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction; and

directing the image toward the display image plane with a final element;

wherein the optical panel comprises a plurality of stacked optical waveguides, each having a first end and a second end, wherein an outlet face is defined by the plurality of first ends, wherein an inlet face is defined by the plurality of second ends, and wherein the optical panel further comprises at least one coupler at the inlet face to redirect light traveling from an axis non-perpendicular to the inlet face to an axis perpendicular to the inlet face.

112. A display system having an optical panel and at least one optical system for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, said display system comprising;

an optical panel, comprising;

a plurality of stacked optical waveguides, each having a first end and a second end, wherein an outlet face is defined by the plurality of first ends, and wherein an inlet face is defined by the plurality of second ends, the inlet face being substantially parallel to the outlet face; and

at least one coupler provided at the inlet face which redirects light traveling from an axis non-perpendicular to the inlet face to an axis perpendicular to the inlet face;

at least one optical system, each said optical system comprising;

an image source;

an imaging element for creating an image from the image source;

an anamorphic telescope for reducing anamorphic distortion of the image, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction; and

a final element for directing the image toward the display image plane.

113. A method for displaying an image onto a display image plane of an optical panel at an incident angle θ

which is greater than zero, said method comprising the steps of;

projecting an image from an image source;

creating an image from the projected image with an imaging element;

reducing anamorphic distortion of the image with an anamorphic element, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction; and

directing the image toward the display image plane with a final element;

wherein the optical panel comprises a plurality of stacked optical waveguides, each having a first end and a second end, wherein an outlet face is defined by the plurality of first ends, wherein an inlet face is defined by the plurality of second ends, the inlet face being substantially parallel to the outlet face, and wherein the optical panel further comprises at least one coupler at the inlet face to redirect light traveling from an axis non-perpendicular to the inlet face to an axis perpendicular to the inlet face.

114. An optical system for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, comprising;

an image source;

an imaging element for creating an image from the image source; and

an anamorphic telescope for reducing anamorphic distortion of the image and for directing the image toward the display image plane, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction.

115. A display system having an optical panel and at least one optical system for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, said display system comprising;

an optical panel, comprising;

a plurality of stacked optical waveguides, each having a first end and a second end, wherein an outlet face is defined by the plurality of first ends, and wherein an inlet face is defined by the plurality of second ends; and

at least one coupler provided at the inlet face which redirects light traveling from an axis non-perpendicular to the inlet face to an axis perpendicular to the inlet face;

at least one optical system, each said optical system comprising;

an image source;

an imaging element for creating an image from the image source; and

an anamorphic telescope for reducing anamorphic distortion of the image and for directing the image toward the display image plane, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction.

116. A display system having an optical panel and at least one optical system for projecting an image onto a display image plane at an incident angle θ

which is greater than zero, said display system comprising;

an optical panel, comprising;

a plurality of stacked optical waveguides, each having a first end and a second end, wherein an outlet face is defined by the plurality of first ends, and wherein an inlet face is defined by the plurality of second ends, the inlet face being substantially parallel to the outlet face; and

at least one coupler provided at the inlet face which redirects light traveling from an axis non-perpendicular to the inlet face to an axis perpendicular to the inlet face;

at least one optical system, each said optical system comprising;

an image source;

an imaging element for creating an image from the image source; and

an anamorphic telescope for reducing anamorphic distortion of the image and for directing the image toward the display image plane, wherein the anamorphic telescope reduces magnification of the image in a first direction and enlarges magnification of the image in a second direction which is perpendicular to the first direction.