3D PROJECTION SYSTEM USING LASER LIGHT SOURCES

• US 20130342904A1
• Filed: 03/14/2012
• Published: 12/26/2013
• Est. Priority Date: 03/14/2011
• Status: Active Grant

• Current Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Original Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Inventors: Richards, Martin J.
• Granted Patent: US 9,696,558 B2
• Time in Patent Office: Days
• US Class Current: 359/464
• CPC Class Codes: G02B 30/23 using wavelength separation, e.g. using anaglyph techniques
• CPC Class Codes: G02B 30/34 Stereoscopes providing a stereoscopic pair of separated images corresponding to parallactically displaced views of the same object, e.g. 3D slide viewers
• CPC Class Codes: H04N 13/324 Colour aspects
• CPC Class Codes: H04N 13/334 using spectral multiplexing
• CPC Class Codes: H04N 13/363 using image projection screens volumetric display H04N13/388

Abstract

Laser or narrow band light sources are utilized to from left (R1, G1, B1) and right (R2,G2;B2,) images of a 3D projection. Under off -axis viewing of projections (i.e. oblique incident angles) the passbands of the viewing filters in the glasses are blue-shifted, which has the potential of cause crosstalk and/or loss of energy/brightness in any channel or color. This blue-shift is compensated via the combined use of any of viewing passbands (220) encompassing the associated projected lightband (222) and a red-shift passband (224) selection of passband wavelengths that maximize usability of the passband as it “shifts” due to varying or increasing angles of off-axis viewing), curvature of viewing filters, and guard bands between light bands of adjacent channels. Implemented with any number of light sources, additional light sources are utilized to affect a desirable increase in color gamut.

Claims

1. A 3D projection system, comprising:

a first set of narrowband light sources;

a second set of narrowband light sources;

a projector configured to, modulate light from the first set of narrowband light sources to produce a first eye channel image of a 3D image, modulate light from the second set of narrowband light sources to produce a second eye channel image of the 3D image, and project the first eye channel image and the second eye channel image for display to a viewer.

2. The 3D projection system according to claim 1, further comprising viewing glasses having passbands wherein light from at least one narrowband light source is passed by each passband and a central wavelength of at least one of the narrowband light sources is blue-shifted compared to a central wavelength of its corresponding passband of the viewing glasses.

3. The 3D projection system according to claim 1, further comprising viewing glasses having passbands wherein light from at least one narrowband light source is passed by each passband and a central wavelength of at least one of the narrowband light sources passed by each passband is blue-shifted compared to a central wavelength of the passband.

4. The 3D projection system according to claim 1, wherein the first narrow band light sources each comprise wavelengths interspersed with wavelengths of the second narrowband light sources and passed at a blue end of corresponding passbands of viewing filters.

5. The 3D projection system according to claim 1, further comprising viewing glasses configured to have passbands corresponding to each of the narrowband light sources, wherein a central wavelength of each passband is red shifted compared to the wavelengths of its corresponding light source.

6. The 3D projection system according to claim 1, wherein the narrowband light sources are laser light sources that are pre-blue shifted compared to passbands of viewing filters configured to separate the first and second eye channels for viewing by the viewer.

7. 3D viewing glasses comprising passbands each configured to pass a corresponding set of projected narrowband wavelengths when viewed normally and when viewed off-axis.

8. The 3D viewing glasses according to claim 7, wherein the passbands are configured to pass wavelengths viewed off-axis by an amount that approximates an oblique viewing angle in a cinema theater.

9. The 3D viewing glasses according to claim 7, wherein the passbands are configured to pass wavelengths viewed not more than a predetermined angle off-axis.

10. The 3D viewing glasses according to claim 9, wherein the predetermined angle is approximately 25 degrees.

11. The 3D viewing glasses according to claim 7, wherein a central wavelength of each set of projected narrowband wavelengths is blue-shifted compared to a central wavelength passed by its corresponding passband.

12. The 3D viewing glasses according to claim 7, wherein a central wavelength of each passband is red-shifted compared to a central wavelength of its corresponding set of projected narrowband wavelengths.

13. The 3D viewing glasses according to claim 11, wherein a tolerance passband is provided between a bluest of the projected narrowband wavelengths in a passband and a blue end of the passband.

14. The 3D viewing glasses according to claim 13, wherein an amount of blueshift is approximately 2×

a bandwidth of the tolerance passband.

15. 3D viewing glasses according to claim 14, wherein the tolerance passband has a bandwidth comprising a maximum deviation in tolerance of the projection system wavelengths.

16. The 3D viewing glasses according to claim 7, wherein a tolerance passband is provided between a bluest of the projected narrowband wavelengths in a passband and a blue end of the passband.

17. The 3D viewing glasses according to claim 16, wherein the tolerance passband is approximately equal to the maximum deviation of filter passband and laser production accuracy.

18. 3D viewing glasses comprising passbands, wherein each passband comprises a narrowband passband intended to pass wavelengths matching a desired lightband, and an off-axis viewing passband, wherein the off-axis viewing passband comprises an area of the passband intended to pass the desired lightband when viewed under conditions causing the passband properties to shift due to off-axis viewing.

19. The 3D viewing glasses according to claim 18, wherein each passband further comprises a tolerance passband passing wavelengths bluer than the desired lightband.

20. The 3D viewing glasses according to claim 19, wherein the tolerance passband is substantially less than the off-axis viewing passband.

21. The 3D viewing glasses according to claim 19 wherein the tolerance passband is configured such that tolerance of the passbands/laser light production, do not cause light to be lost from the passbands.

22. The 3D viewing glasses according to claim 19, wherein the tolerance passband comprises approximately ⅕

th the passband bandwidth of the off-axis viewing passband.

23. The 3D viewing glasses according to claim 19, wherein the tolerance passband bandwidth is a function of variability of accuracy and quality of the passbands and/or lightbands.

24. The 3D viewing glasses according to claim 19, wherein the tolerance passband comprises approximately ⅕

th the passband bandwidth of the off-axis viewing passband.

25. The 3D viewing glasses according to claim 18, wherein the passbands comprise a first set of 4 passbands respectively intended to pass at least 6 sets of narrowband lights.

26. The 3D viewing glasses according to claim 18, wherein the passbands are constructed from glass with layers disposed thereon, and wherein the wavelength properties change according to location on the lenses.

27. The 3D viewing glasses according to claim 18, wherein the off-axis viewing is approximately 25 degrees.

28. The 3D viewing glasses according to claim 27, wherein the off-axis passband is reduced by an amount of curvature and wavelength properties according to location on the filters.

29. The 3D viewing glasses according to claim 18, wherein the glasses lenses are a plastic or plastic-like material, altering the passband properties of the glasses in a central area in comparison to the edges.

30. The 3D viewing glasses according to claim 18, wherein the glasses lenses are a plastic or plastic-like material, and the plastic material is stretched to alter the passband properties of the glasses in a central area in comparison to the edges of the material.

31. The 3D viewing glasses according to claim 18, wherein the filters are disposed on arc shaped lenses of the glasses.

32. The 3D viewing glasses according to claim 18, wherein the filters are in an arc by a frame of the glasses.

33. The 3D viewing glasses according to claim 18, wherein the filters are held in a cylindrical curve by the glasses.

34. The 3D viewing glasses according to claim 18, wherein the filters are disposed on cylindrically curved lenses of the glasses.

35. The 3D viewing glasses according to claim 18, wherein at least one passband encompasses multiple desired lightbands.

36. The 3D viewing glasses according to claim 35, wherein at least one passband encompasses a desired lightband and a second desired lightband, and 2 off-axis viewing passbands, wherein a first of the off-axis viewing passbands comprises a passband “

redder”

than the first desired lightband and “

bluer”

than the second desired lightband, and a second of the off-axis viewing passbands is “

redder”

than both the first and second desired lightbands.

37. The 3D viewing glasses according to claim 36, wherein the first off-axis viewing passband passes more wavelengths than the second off-axis viewing passband.

38. The 3D viewing glasses according to claim 37, wherein the passband encompassing the desired lightband and second desired light band is part of a first filter in the glasses and are surrounded by a red high pass passband and a green passband in a second filter of the glasses.

39. The 3D viewing glasses according to claim 36, wherein the desired lightbands provide a color space approximately equivalent to that illustrated in FIGS. 4B and 5B.

40. The 3D viewing glasses according to claim 18, wherein at least 3 desired lightbands are passed by each filter using only 2 passbands.

41. Glasses comprising lenses having passbands configured to pass desired lightbands off center in the passband when viewed normally such that off-axis viewing “

moves”

the filter to center the desired wavelength.

42. The Glasses according to claim 41, wherein each lens comprises 2 passbands configured to pass at least 3 narrowband lights.

43. The Glasses according to claim 42, wherein the narrowband lights are modulated laser lights.

44. The Glasses according to claim 42, wherein the narrowband lights comprise portions of a 3D image.

45. The Glasses according to claim 42, wherein a first of the lenses comprises a blue passband and a green-red passband, and a second of the lenses comprises a blue-green passband and a red passband.

46. The Glasses according to claim 45, wherein the red passband comprises a high pass filter.

47. The Glasses according to claim 41, wherein the desired lightbands comprise a “

blue”

of center lightband and a “

red”

of center lightband.

48. A filter having passbands configured to pass desired narrowband lightbands in “

bluer”

wavelength areas of the passbands when viewed normally, and off-axis viewing shifts the passbands such that the desired lightbands are viewed in “

redder”

areas of the passbands.

49. The filter according to claim 48, wherein the filter is intended to be used in viewing a left or right image of a 3D image.

50. The filter according to claim 48, wherein the filter is mounted in a lens position of viewing glasses.

51. Viewing glasses, comprising:

a left eye filter configured to pass light wavelengths corresponding to a left eye channel of a 3D image; and

a right eye filter configured to pass light wavelengths corresponding to a right eye channel of a 3D image;

wherein the filters each comprise a set of passbands, each passband respectively corresponding to and configured to pass at least one desired narrowband light; and

a central wavelength passed by each passband is offset red compared to an average wavelength of its corresponding desired lightband(s).

52. The viewing glasses according to claim 51, wherein each desired lightband comprises a narrow lightband.

53. The viewing glasses according to claim 51, wherein each desired lightband comprises laser light.

54. The viewing glasses according to claim 51, wherein each desired light band originates with a laser light source.

55. The viewing glasses according to claim 51, wherein each desired light band originates with a separate light source.

56. The viewing glasses according to claim 51, wherein the filters on each lens comprise at least one blue only filter or at least one red only filter.

57. The viewing glasses according to claim 51, wherein the filters on each lens comprise only one blue only filter or only one red only filter.

58. The viewing glasses according to claim 51, wherein the filters on each lens comprise only one blue only filter and no red only filters or only one red only filter and no blue only filters.

59. The viewing glasses according to claim 51, wherein the filters on each lens comprise at least one blue filter or at least one red filter, and a filter comprising two other primary colors.

60. The viewing glasses according to claim 51, wherein each of the filters comprise at least one single color passband and at least one two color passband each passband including a portion of the passband dedicated to normal axis viewing of wavelengths corresponding to its channel and an off-axis viewing portion dedicated to off-axis viewing of wavelengths corresponding to its channel.

61. The viewing glasses according to claim 60, wherein a “

bluest”

of the filters for one of the channels is configured to pass at least two desired lightbands separated by at least one off-axis viewing portion.

62. The viewing glasses according to claim 61, wherein the “

bluest”

of the filters for one of the channels is “

surrounded”

by a blue only passband and a green-red passband of the other channel.

63. The viewing glasses according to claim 60, wherein a “

reddest”

of the filters for one of the channels is configured to pass at least two desired lightbands separated by at least one off-axis viewing portion.

64. 3D viewing glasses comprising a first eye filter comprising passbands for passing primary color lights, wherein each passband comprises a passband portion for viewing narrowband light normally and an off-axis passband portion configured for viewing the narrowband light off-axis.

65. The 3D viewing glasses according to claim 64, wherein the off-axis passband portion is wide enough to pass off-axis viewing of the narrowband light at a predetermined angle.

66. The 3D viewing glasses according to claim 65, wherein the predetermined off-axis viewing angle is approximately 25 degrees.

67. The 3D viewing glasses according to claim 65, wherein the off-axis passband passes longer wavelengths than the passband configured to pass the narrowband light normally.

68. The 3D viewing glasses according to claim 65, further comprising a tolerance passband approximately ⅕

th in size compared to the off-axis passband and passing shorter wavelengths than the passband configured to pass the narrowband light normally.

69. 3D viewing glasses comprising a first eye filter comprising passbands for passing primary color lights and having a passband comprising an open end and a closed end configured to pass a narrowband light wherein the passband includes a tolerance passband and a shift passband having at least twice the bandwidth of the tolerance passband.

70. The 3D viewing glasses according to claim 69, further comprising a second filter configured to pass primary lights including a second passband having an open end and a closed end.

71. The 3D viewing glasses according to claim 70, wherein the second passband is at an opposite spectral end compared to the first passband.

72. The 3D viewing filter according to claim 70, wherein the second passband is in blue wavelengths and the first passband is in red wavelengths.

73. 3D viewing glasses comprising a viewing filter comprising passbands for passing primary color lights and having a passband comprising an open end and a closed end configured to pass a narrowband light wherein the passband includes a tolerance passband and a shift passband, the shift passband comprising a bandwidth approximately equal to an amount of blueshift that occurs when viewing at a predetermined angle.

74. The 3D viewing glasses according to claim 73, wherein the predetermined angle comprises a maximum oblique angle of viewing through the glasses when viewing a cinema screen.

75. The 3D viewing glasses according to claim 73, wherein the predetermined angle comprises an average oblique angle of viewing by an average cinema theater viewer when seated at the end of a seat row in the theater.

76. The 3D viewing glasses according to claim 73, wherein the predetermined angle comprises an average oblique angle of viewing by a cinema theater viewer when facing one direction and viewing an image projected with the primary color lights in another direction through the glasses.

77. 3D viewing glasses comprising at least two passbands, including a first passband having an open end and a closed end, and second passband having an open end and a closed end.

78. The 3D viewing glasses according to claim 77, wherein the first and second passbands are on different filters of the glasses.

79. The 3D viewing glasses according to claim 77, wherein the first and second passbands are at opposite spectral locations.

80. The 3D viewing glasses according to claim 79, wherein the first and second passbands are on a same filter of the glasses.

81. The 3D viewing glasses according to claim 77, wherein the first passband comprises a tolerance band at the closed end of the first passband.

82. The 3D viewing glasses according to claim 77, wherein the second passband comprises a shifting passband, at the closed end of the second passband, only intended to pass primary light viewed at off-perpendicular angles through the glasses.

83. The 3D viewing glasses according to claim 77, wherein the first passband comprises a tolerance passband at the closed end of the first passband and the second passband comprises a shifting passband at the closed end of the second passband.

84. 3D glasses comprising:

a first eye lens comprising a first pass filter at an end of visible wavelengths; and

a second eye lens comprising a second pass filter at an opposite end of visible wavelengths.

85. The 3D glasses according to claim 84, wherein one of the pass filters comprises a shifting pass area from a wavelength intended to be passed by the filter and a closed end of the pass filter.

86. The 3D glasses according to claim 84, wherein one of the pass filters comprises a shifting pass area from a wavelength intended to be passed by the filter and continuing without visible pass limit toward the end of the visible spectrum.

87. The 3D glasses according to claim 84, wherein the first eye lens and second eye lens each further comprise an additional passband configured to pass green light.

88. A 3D filter material comprising a high pass filter in red wavelengths, and a low pass filter in blue wavelengths.

89. The 3D filter material of claim 88, further comprising a bandpass filter in green wavelengths.

90. The 3D filter material of claim 88, wherein the open ended low pass filter is specifically configured to pass a narrow band blue light with a shifting pass area beginning at a wavelength of a “

red wall”

of the filter and continuing to the wavelength of the narrow band blue light.

91. The 3D filter material of claim 88, wherein the filter material is part of a filter material set comprising a second filter material comprising one of, a blue-green passband and a red passband, and a green-red passband and a blue passband.

92. The 3D filter material according to claim 88, further comprising a green passband.

93. The 3D filter material according to claim 88, wherein the open ended high pass filter is specifically configured to utilize the open ended portion of the high pass filter passing wavelengths higher than a wavelength intended to be passed by the open ended high pass filter as a shifting pass area.

94. The 3D filter material according to any of claims 90 and 93, wherein the shifting pass area is sufficient to pass off-axis viewed lights at a predetermined angle.

95. The 3D filter material according to claim 94, wherein the predetermined angle comprises an angle of approximately 25 degrees.

96. The 3D filter material according to claim 94, wherein the predetermined angle comprises one of a maximum off-axis viewing angle for typical viewing styles, an average off-axis viewing angle, and an acceptable off-axis viewing angle at a venue.

97. The 3D filter material according to claim 94, wherein the predetermined angle comprises a trade-off between available spectrum for shifting pass areas and off-axis viewing quality such that given the number of passbands and guard band sizes to prevent crosstalk between 3D channels, the filter material provides the maximum off-axis viewing capability and colorspace.