US6183091B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Color imaging systems and methods
Assignee: RealD Inc
•
Filing: 1999-05-14
•
Granted: 2001-02-06
•
Expires: 2019-05-14
Abstract
Abstract A system for separating light into different spectrums and for recombining the light includes at least one polarizing beamsplitter and at least one retarder stack configured to condition the polarization of input light differently for different spectrums. A device embodying the invention could utilize multiple polarizing beamsplitters and multiple retarder stacks. Alternatively, a system could utilize a single polarizing beamsplitter and a single retarder stack in combination with one or more dichroic beamsplitters. In preferred embodiments, one or more reflective modulator panels are included to separately modulate each separated spectrum of light. Such an embodiment can be used for a color projection system. In each of the embodiments that utilize modulators, distances between the modulators and the focusing optics is essentially the same.
Inventors
- 👤 Kristina M. Johnson
- 👤 Gary D. Sharp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:22
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/3105; G; G02; G02B; G02B27/00; G02B27/28; G02B27/283; G03; G03B; G03B21/00; G03B21/14; G03B21/20; G03B21/2073; G03B33/00; G03B33/10; G03B33/12; H04N9/3141; H04N9/315; H04N9/3167
Claims Analysis
Total Claims: 68
Claim 1
Independent Claim
118 words
A system for separating and combining three spectrums of light, comprising: first, second, third and fourth polarizing beamsplitters, wherein each polarizing beamsplitter is configured to allow light having a first polarization orientation to pass therethrough, wherein each polarizing beamsplitter is configured to reflect light having a second polarization orientation, and wherein each polarizing beamsplitter has two interior sides adjacent two other polarizing beamsplitters, and two exterior sides that are not adjacent other polarizing beamsplitters; and a first retarder stack located adjacent an exterior side of the first polarizing beamsplitter; a second retarder stack located adjacent an interior side of the first polarizing beamsplitter; and a third retarder stack located between interior sides of two of the polarizing beamsplitters.
Claim 2
Independent Claim
118 words
A system for separating and combining three spectrums of light, comprising: first, second, third and fourth polarizing beamsplitters, wherein each polarizing beamsplitter is configured to allow light having a first polarization orientation to pass therethrough, wherein each polarizing beamsplitter is configured to reflect light having a second polarization orientation, and wherein each polarizing beamsplitter has two interior sides adjacent two other polarizing beamsplitters, and two exterior sides that are not adjacent other polarizing beamsplitters; and a first retarder stack located adjacent an exterior side of the first polarizing beamsplitter; a second retarder stack located adjacent an interior side of the first polarizing beamsplitter; and a third retarder stack located between interior sides of two of the polarizing beamsplitters.
Claim 3
Dependent Claim
22 words
The system of claim 1 , further comprising a fourth retarder stack located adjacent an exterior side of the fourth polarizing beamsplitter.
Claim 4
Dependent Claim
17 words
The system of claim 2 , wherein the first and fourth retarder stacks have substantially similar characteristics.
Claim 5
Dependent Claim
17 words
The system of claim 1 , wherein the second and third retarder stacks have substantially similar characteristics.
Claim 6
Dependent Claim
29 words
The system of claim 1 , further comprising first, second and third reflective modulator panels configured to selectively rotate the polarization orientation of reflected light in a spatial pattern.
Claim 7
Dependent Claim
24 words
The system of claim 5 , wherein the first reflective modulator panel is located adjacent an exterior side of one of the polarizing beamsplitters.
Claim 8
Dependent Claim
24 words
The system of claim 6 , wherein the second reflective modulator panel is located adjacent an exterior side of one of the polarizing beamsplitters.
Claim 9
Dependent Claim
40 words
The system of claim 7 , wherein the third reflective modulator panel is located adjacent an exterior side of one of the polarizing beamsplitters that also has one of the first and second modulator panels adjacent its other exterior side.
Claim 10
Dependent Claim
27 words
The system of claim 5 , further comprising first, second and third light doublers that are paired, respectively, with the first, second and third reflective modulator panels.
Claim 11
Dependent Claim
21 words
The system of claim 1 , further comprising an input polarizer, located adjacent the first retarder stack, for polarizing input light.
Claim 12
Dependent Claim
38 words
The system of claim 1 , wherein the first retarder stack is configured to receive polarized input light and to output a first spectrum in the first polarization orientation and a second spectrum in the second polarization orientation.
Claim 13
Dependent Claim
76 words
The system of claim 11 , wherein the first polarizing beamsplitter is arranged to receive the light output from the first retarder stack in a first direction, and wherein the first polarizing beamsplitter is configured to allow light in the first spectrum, having the first polarization orientation, to pass therethrough in the first direction, and to reflect light in the second spectrum, having the second polarization orientation, in a second direction towards the third polarizing beamsplitter.
Claim 14
Dependent Claim
69 words
The system of claim 12 , wherein the second polarizing beamsplitter is arranged to receive the light in the first spectrum, passing through the first polarizing beamsplitter in the first direction, and wherein the second polarizing beamsplitter is configured to reflect light having the second polarization orientation, and passing in a third direction that is opposite to the first direction, in the second direction towards the fourth polarizing beamsplitter.
Claim 15
Dependent Claim
65 words
The system of claim 13 , further comprising a reflective modulator panel arranged on an exterior side of the second polarizing beamsplitter, wherein the first reflective modulator panel is configured to reflect incident light passing in the first direction so that it leaves the modulator panel in the third direction, and to selectively modulate the polarization orientation of the reflected light in a spatial pattern.
Claim 16
Dependent Claim
82 words
The system of claim 13 , wherein the second retarder stack is arranged to receive the light in the second spectrum, having the second polarization orientation, that is reflected by the first polarizing beamsplitter, wherein the second retarder stack is configured to allow a third spectrum of the light to pass therethrough without a change in its polarization orientation, and wherein the second retarder stack is configured to change the polarization orientation of a fourth spectrum back to the first polarization orientation.
Claim 17
Dependent Claim
89 words
The system of claim 15 , wherein the third polarizing beamsplitter is configured to reflect light passing in the second direction and having the second polarization orientation so that it travels in the third direction, wherein the third polarizing beamsplitter is configured to reflect light passing in a fourth direction, opposite to the second direction, so that it travels in the first direction towards the fourth polarizing beamsplitter, and wherein the third polarizing beamsplitter is configured to allow light having the first polarization orientation to pass therethrough without deflection.
Claim 18
Dependent Claim
140 words
The system of claim 16 , further comprising a first reflective modulator panel arranged on an exterior side of the third polarizing beamsplitter opposite the first polarizing beamsplitter, and a second reflective modulator panel arranged on an exterior side of the third polarizing beamsplitter opposite the fourth polarizing beamsplitter, wherein the first reflective modulator panel is configured to reflect incident light passing in the second direction so that it leaves the first reflective modulator panel in the fourth direction, and to selectively modulate the polarization orientation of the reflected light in a spatial pattern, and wherein the second reflective modulator panel is configured to reflect incident light passing in the third direction so that it leaves the second reflective modulator panel in the first direction, and to selectively modulate the polarization orientation of the reflected light in a spatial pattern.
Claim 19
Dependent Claim
86 words
The system of claim 16 , wherein the third retarder stack is arranged to receive light passing from the third polarizing beamsplitter towards the fourth polarizing beamsplitter, wherein the third retarder stack is configured to allow light in the third spectrum, having the first polarization orientation, to pass therethrough without a change in its polarization orientation, and wherein the third retarder stack is configured to change the polarization orientation of the light in the fourth spectrum from the second polarization orientation to the first polarization orientation.
Claim 20
Dependent Claim
54 words
The system of claim 18 , wherein the fourth polarizing beamsplitter is configured to allow the light in the third and fourth spectrums to pass therethrough without deflection, and wherein the fourth polarizing beamsplitter is configured to reflect light in the first spectrum passing in the second direction, and having the second polarization orientation.
Claim 21
Dependent Claim
95 words
The system of claim 19 , further comprising a fourth retarder stack arranged adjacent an exterior side of the fourth polarizing beamsplitter and arranged to receive light in the first, third and fourth spectrums passing from the fourth polarizing beamsplitter, wherein the fourth retarder stack is configured to allow light in the third and fourth spectrums to pass therethrough without a change in their polarization orientation, and wherein the fourth retarder stack is configured to change the polarization orientation of light in the first spectrum from the second polarization orientation to the first polarization orientation.
Claim 22
Dependent Claim
25 words
The system of claim 1 , wherein at least one of the first, second and third retarder stacks reflects or blocks selected wavelengths of light.
Claim 23
Dependent Claim
25 words
The system of claim 21 , wherein the reflected or blocked wavelengths of light are located substantially between the first and third spectrums of light.
Claim 24
Dependent Claim
25 words
The system of claim 21 , wherein the reflected or blocked wavelengths of light are located substantially between the third and fourth spectrums of light.
Claim 25
Dependent Claim
133 words
A color projection system, comprising: first, second, third and fourth polarizing beamsplitters, arranged in a square pattern, wherein each polarizing beamsplitter is configured to allow light having a first polarization orientation to pass therethrough, wherein each polarizing beamsplitter is configured to reflect light having a second polarization orientation, and wherein each polarizing beamsplitter has two interior sides adjacent two other polarizing beamsplitters, and two exterior sides that are not adjacent other polarizing beamsplitters; a first retarder stack located on an exterior side of the first polarizing beamsplitter; a second retarder stack located adjacent an interior side of the first polarizing beamsplitter; a third retarder stack located between interior sides of two of the polarizing beamsplitters; a light source located adjacent the first retarder stack; and projection optics located adjacent the fourth polarizing beamsplitter.
Claim 26
Dependent Claim
133 words
A color projection system, comprising: first, second, third and fourth polarizing beamsplitters, arranged in a square pattern, wherein each polarizing beamsplitter is configured to allow light having a first polarization orientation to pass therethrough, wherein each polarizing beamsplitter is configured to reflect light having a second polarization orientation, and wherein each polarizing beamsplitter has two interior sides adjacent two other polarizing beamsplitters, and two exterior sides that are not adjacent other polarizing beamsplitters; a first retarder stack located on an exterior side of the first polarizing beamsplitter; a second retarder stack located adjacent an interior side of the first polarizing beamsplitter; a third retarder stack located between interior sides of two of the polarizing beamsplitters; a light source located adjacent the first retarder stack; and projection optics located adjacent the fourth polarizing beamsplitter.
Claim 27
Dependent Claim
22 words
The system of claim 24 , further comprising a fourth retarder stack located adjacent an exterior side of the fourth polarizing beamsplitter.
Claim 28
Dependent Claim
29 words
The system of claim 24 , further comprising first, second and third reflective modulator panels configured to selectively rotate the polarization orientation of reflected light in a spatial pattern.
Claim 29
Dependent Claim
31 words
The system of claim 26 , wherein the system is configured so that substantially equal distances exist between the projection optics and each of the first, second and third modulator panels.
Claim 30
Dependent Claim
42 words
The system of claim 26 , wherein the first reflective modulator panel is located adjacent an exterior side of one polarizing beamsplitter, and wherein the second and third reflective modulator panels are located adjacent exterior sides of another of the polarizing beamsplitters.
Claim 31
Dependent Claim
27 words
The system of claim 26 , further comprising first, second and third light doublers that are paired, respectively, with the first, second and third reflective modulator panels.
Claim 32
Independent Claim
51 words
A system for separating and combining three spectrums of light, comprising: a polarizing beamsplitter; an input retarder stack located adjacent a first side of the polarizing beamsplitter; a spacer located adjacent a second side of the polarizing beamsplitter; and a dichroic beamsplitter located adjacent a third side of the polarizing beamsplitter.
Claim 33
Independent Claim
51 words
A system for separating and combining three spectrums of light, comprising: a polarizing beamsplitter; an input retarder stack located adjacent a first side of the polarizing beamsplitter; a spacer located adjacent a second side of the polarizing beamsplitter; and a dichroic beamsplitter located adjacent a third side of the polarizing beamsplitter.
Claim 34
Dependent Claim
21 words
The system of claim 30 , further comprising an output retarder stack located adjacent a fourth side of the polarizing beamsplitter.
Claim 35
Dependent Claim
17 words
The system of claim 31 , wherein the input and output retarder stacks have substantially similar characteristics.
Claim 36
Dependent Claim
29 words
The system of claim 30 , further comprising first, second and third reflective modulator panels configured to selectively rotate the polarization orientation of reflected light in a spatial pattern.
Claim 37
Dependent Claim
59 words
The system of claim 33 , wherein the first reflective modulator panel is located adjacent a side of the spacer opposite the polarizing beamsplitter, wherein the second reflective modulator panel is located adjacent a first exterior side of the dichroic beamsplitter, and wherein the third reflective modulator panel is located adjacent a second exterior side of the dichroic beamsplitter.
Claim 38
Dependent Claim
27 words
The system of claim 34 , further comprising first, second and third light doublers that are paired, respectively, with the first, second and third reflective modulator panels.
Claim 39
Dependent Claim
45 words
The system of claim 34 , further comprising first and second light doublers, wherein the first light doubler operates on light modulated by the first reflective modulator panel, and wherein the second light doubler operates on light modulated by the second and third modulator panels.
Claim 40
Dependent Claim
20 words
The system of claim 36 , wherein the first light doubler is located between the polarizing beamsplitter and the spacer.
Claim 41
Dependent Claim
22 words
The system of claim 36 , wherein the first light doubler is located between the spacer and the first reflective modulator panel.
Claim 42
Dependent Claim
21 words
The system of claim 36 , wherein the second light doubler is located between the polarizing beamsplitter and the dichroic beamsplitter.
Claim 43
Dependent Claim
21 words
The system of claim 30 , further comprising an input polarizer, located adjacent the input retarder stack, for polarizing input light.
Claim 44
Dependent Claim
22 words
The system of claim 30 , further comprising a polarization conversion system, located adjacent the input retarder stack for polarizing input light.
Claim 45
Dependent Claim
22 words
The system of claim 41 , further comprising a clean-up polarizer located between the polarization conversion system and the input retarder stack.
Claim 46
Dependent Claim
47 words
The system of claim 30 , wherein the first retarder stack is configured to receive polarized input light passing in a first direction, and to output a first spectrum of light in a first polarization orientation and a second spectrum of light in a second polarization orientation.
Claim 47
Dependent Claim
118 words
The system of claim 43 , wherein the polarizing beamsplitter is configured to direct light having the first polarization orientation that is received from the input retarder stack towards the spacer, wherein the polarizing beamsplitter is configured to direct any light having the second polarization orientation that is received from the input retarder stack towards the dichroic beamsplitter, wherein the polarizing beamsplitter is configured to direct any light having the second polarization orientation that is received from the spacer towards a fourth side of the polarizing beamsplitter, and wherein the polarizing beamsplitter is configured to direct any light having the first polarization orientation that is received from the dichroic beamsplitter towards the fourth side of the polarizing beamsplitter.
Claim 48
Dependent Claim
115 words
The system of claim 44 , wherein the dichroic beamsplitter is configured to receive the light in the second spectrum, having the second polarization orientation, from the polarizing beamsplitter, to direct a third spectrum of the received light toward a first exterior side of the dichroic beamsplitter and to direct a fourth spectrum of the received light toward a second exterior side of the dichroic beamsplitter, wherein the dichroic beamsplitter is configured to direct any light in the third spectrum returned from the first exterior side towards the polarizing beamsplitter, and wherein the dichroic beamsplitter is configured to direct any light in the fourth spectrum returned from the second exterior side towards the polarizing beamsplitter.
Claim 49
Dependent Claim
76 words
The system of claim 45 , further comprising a first reflective modulator panel located adjacent the first exterior side of the dichroic beamsplitter, and a second reflective modulator panel located adjacent the second exterior side of the dichroic beamsplitter, wherein the first reflective modulator panel is configured to reflect and selectively modulate light in the third spectrum, and wherein the second reflective modulator panel is configured to reflect and selectively modulate light in the fourth spectrum.
Claim 50
Dependent Claim
43 words
The system of claim 46 , further comprising a third reflective modulator panel, located adjacent an exterior side of the spacer opposite the polarizing beamsplitter, wherein the third reflective modulator panel is configured to reflect and selectively modulate light in the first spectrum.
Claim 51
Dependent Claim
65 words
A color projection system, comprising: a polarizing beamsplitter; an input retarder stack located adjacent a first side of the polarizing beamsplitter; a light source located adjacent the first retarder stack; a spacer located adjacent a second side of the polarizing beamsplitter; a dichroic beamsplitter located adjacent a third side of the polarizing beamsplitter; and projection optics located adjacent a fourth side of the polarizing beamsplitter.
Claim 52
Dependent Claim
65 words
A color projection system, comprising: a polarizing beamsplitter; an input retarder stack located adjacent a first side of the polarizing beamsplitter; a light source located adjacent the first retarder stack; a spacer located adjacent a second side of the polarizing beamsplitter; a dichroic beamsplitter located adjacent a third side of the polarizing beamsplitter; and projection optics located adjacent a fourth side of the polarizing beamsplitter.
Claim 53
Dependent Claim
29 words
The system of claim 48 , further comprising first, second and third reflective modulator panels configured to selectively rotate the polarization orientation of reflected light in a spatial pattern.
Claim 54
Dependent Claim
57 words
The system of claim 49 , wherein the first reflective modulator panel is located adjacent a side of the spacer opposite the polarizing beamsplitter, wherein the second reflective modulator panel is located adjacent a first side of the dichroic beamsplitter, and wherein the third reflective modulator panel is located adjacent a second side of the dichroic beamsplitter.
Claim 55
Dependent Claim
27 words
The system of claim 50 , further comprising first, second and third light doublers that are paired, respectively, with the first, second and third reflective modulator panels.
Claim 56
Dependent Claim
46 words
The system of claim 50 , further comprising first and second light doublers, wherein the first light doubler operates on light modulated by the first reflective modulator panel, and wherein the second light doubler operates on light modulated by the second and third reflective modulator panels.
Claim 57
Dependent Claim
21 words
The system of claim 48 , further comprising an output retarder stack located adjacent a fourth side of the polarizing beamsplitter.
Claim 58
Dependent Claim
31 words
The system of claim 47 , wherein an output retarder stack is configured to ensure that the polarization orientation of light in the first, third and fourth spectrums is the same.
Claim 59
Independent Claim
146 words
A method of separating, modulating and re-combining spectrums of light, comprising the steps of: conditioning input light with a first retarder stack so that input light in a first spectrum has a first polarization orientation, and input light in a second spectrum has a second polarization orientation; separating the light in the first spectrum from the light in the second spectrum using a polarizing beamsplitter; conditioning the separated light in the second spectrum using a second retarder stack so that light in a third spectrum has the first polarization orientation, and light in a fourth spectrum has the second polarization orientation; separating the light in the third spectrum from the light in the fourth spectrum using a polarizing beamsplitter; modulating light in the first, third and fourth spectrums separately, using first, second and third modulators; and recombining the first, third and fourth modulated spectrums of light.
Claim 60
Independent Claim
146 words
A method of separating, modulating and re-combining spectrums of light, comprising the steps of: conditioning input light with a first retarder stack so that input light in a first spectrum has a first polarization orientation, and input light in a second spectrum has a second polarization orientation; separating the light in the first spectrum from the light in the second spectrum using a polarizing beamsplitter; conditioning the separated light in the second spectrum using a second retarder stack so that light in a third spectrum has the first polarization orientation, and light in a fourth spectrum has the second polarization orientation; separating the light in the third spectrum from the light in the fourth spectrum using a polarizing beamsplitter; modulating light in the first, third and fourth spectrums separately, using first, second and third modulators; and recombining the first, third and fourth modulated spectrums of light.
Claim 61
Independent Claim
111 words
A method of separating, modulating, and re-combining spectrums of light, comprising the steps of: conditioning input light with a first retarder stack so that input light in a first spectrum has a first polarization orientation, and input light in a second spectrum has a second polarization orientation; separating the light in the first spectrum from the light in the second spectrum using a polarizing beamsplitter; separating light in the separated second spectrum into third and fourth spectrums of light with a dichroic beamsplitter; modulating the light in the first, third and fourth spectrums separately, using first, second and third modulators; and recombining the first, third and fourth modulated spectrums of light.
Claim 62
Independent Claim
111 words
A method of separating, modulating, and re-combining spectrums of light, comprising the steps of: conditioning input light with a first retarder stack so that input light in a first spectrum has a first polarization orientation, and input light in a second spectrum has a second polarization orientation; separating the light in the first spectrum from the light in the second spectrum using a polarizing beamsplitter; separating light in the separated second spectrum into third and fourth spectrums of light with a dichroic beamsplitter; modulating the light in the first, third and fourth spectrums separately, using first, second and third modulators; and recombining the first, third and fourth modulated spectrums of light.
Claim 63
Independent Claim
89 words
A system for separating input light into multiple spectra, comprising: first, second, third and fourth polarizing beamsplitters, wherein each polarizing beamsplitter is configured to allow light having a first polarization orientation to pass therethrough, and wherein each polarizing beamsplitter is configured to reflect light having a second polarization orientation; and first, second and third retarder stacks, wherein the first, second, third and fourth polarizing beamsplitters and the first, second and third retarder stacks are arranged and optically coupled such that said input light is separated into said multiple spectra.
Claim 64
Independent Claim
89 words
A system for separating input light into multiple spectra, comprising: first, second, third and fourth polarizing beamsplitters, wherein each polarizing beamsplitter is configured to allow light having a first polarization orientation to pass therethrough, and wherein each polarizing beamsplitter is configured to reflect light having a second polarization orientation; and first, second and third retarder stacks, wherein the first, second, third and fourth polarizing beamsplitters and the first, second and third retarder stacks are arranged and optically coupled such that said input light is separated into said multiple spectra.
Claim 65
Independent Claim
40 words
A system for separating and combining multiple spectra of light, comprising: a polarizing beamsplitter; an input retarder stack located adjacent a first side of the polarizing beamsplitter; and a dichroic beamsplitter located adjacent a second side of the polarizing beamsplitter.
Claim 66
Independent Claim
40 words
A system for separating and combining multiple spectra of light, comprising: a polarizing beamsplitter; an input retarder stack located adjacent a first side of the polarizing beamsplitter; and a dichroic beamsplitter located adjacent a second side of the polarizing beamsplitter.
Claim 67
Independent Claim
84 words
A system for combining multiple input spectra, comprising: first, second, third and fourth polarizing beamsplitters, wherein each polarizing beamsplitter is configured to allow light having a first polarization orientation to pass therethrough, and wherein each polarizing beamsplitter is configured to reflect light having a second polarization orientation; and first, second and third retarder stacks, wherein the first, second, third and fourth polarizing beamsplitters and the first, second and third retarder stacks are arranged and optically coupled such that said multiple input spectra are combined.
Claim 68
Independent Claim
84 words
A system for combining multiple input spectra, comprising: first, second, third and fourth polarizing beamsplitters, wherein each polarizing beamsplitter is configured to allow light having a first polarization orientation to pass therethrough, and wherein each polarizing beamsplitter is configured to reflect light having a second polarization orientation; and first, second and third retarder stacks, wherein the first, second, third and fourth polarizing beamsplitters and the first, second and third retarder stacks are arranged and optically coupled such that said multiple input spectra are combined.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-02-06 | 2004-08-07 | 2005-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-02-06 | 2008-08-07 | 2009-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-02-06 | 2012-08-07 | 2013-02-06 | $7700.00 | Window Closed / Lapsed |