US4962997A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Three color separation using subtractive dichroic beamsplitters
Assignee: HP Inc
•
Filing: 1988-04-21
•
Granted: 1990-10-16
•
Expires: 2008-04-21
Abstract
Abstract A structure is provided which receives light from a single source, separates the light into components, modulates the components with image information, and recombines the resultant image beams in order to form a multi-colored image. A small optical path length is provided for each of the separated beams, and small physical size is realized, without the use of crossed beamsplitters, with their attendant cost and performance limitations.
Inventors
- 👤 Richard R. Baldwin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:13
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/3105; G; G02; G02B; G02B27/00; G02B27/10; G02B27/1006; G02B27/102; G02B27/1046; G02B27/14; G02B27/145; G02B5/00; G02B5/20; G02B5/28
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
293 words
An optical transmission system comprising: a light source for providing a first, a second, and a third color of light; a first means for passing in a first direction said second and third colors of light while passing in a second direction said first color of light as a separated first color source, said first means comprising a filter which passes said first color and reflects said second and third colors in a single direction; a second means for passing in a first direction said second color of light as a separated second color source while passing in a second direction said third color of light as a separated third color source; a first image light valve means for receiving light from said separated first color source and modulating said light with image information to provide a first image beam of said first color; a second image light valve means for receiving light from said separated second color source and modulating said light with image information to provide a second image beam of said second color; a third image light valve means for receiving light from said separated third color source and modulating said light with image information to provide a third image beam of said third color; and means for combining said first, second, and third image beams to provide a multi-colored image beam, wherein said means for combining comprises: a first filter which passes a first one of said image beams and reflects a second one of said image beams; and a second filter which passes said first and second ones of said image beams and reflects a third one of said image beams, wherein none of said first, second or third color of light impinge upon more than three filters.
Claim 2
Dependent Claim
293 words
An optical transmission system comprising: a light source for providing a first, a second, and a third color of light; a first means for passing in a first direction said second and third colors of light while passing in a second direction said first color of light as a separated first color source, said first means comprising a filter which passes said first color and reflects said second and third colors in a single direction; a second means for passing in a first direction said second color of light as a separated second color source while passing in a second direction said third color of light as a separated third color source; a first image light valve means for receiving light from said separated first color source and modulating said light with image information to provide a first image beam of said first color; a second image light valve means for receiving light from said separated second color source and modulating said light with image information to provide a second image beam of said second color; a third image light valve means for receiving light from said separated third color source and modulating said light with image information to provide a third image beam of said third color; and means for combining said first, second, and third image beams to provide a multi-colored image beam, wherein said means for combining comprises: a first filter which passes a first one of said image beams and reflects a second one of said image beams; and a second filter which passes said first and second ones of said image beams and reflects a third one of said image beams, wherein none of said first, second or third color of light impinge upon more than three filters.
Claim 3
Dependent Claim
293 words
An optical transmission system comprising: a light source for providing a first, a second and a third color of light; a first means for passing in a first direction said second and third colors of light while passing in a second direction said first color of light as a separated first color source, said first means comprising a filter which passes said first color and reflects said second and third colors in a single direction; a second means for passing in a first direction said second color of light as a separated second color source while passing in a second direction said third color of light as a separated third color source; a first image light valve means for receiving light from said separated first color source and modulating said light with image information to provide a first image beam of said first color; a second image light valve means for receiving light from said separated second color source and modulating said light with image information to provide a second image beam of said second color; a third image light valve means for receiving light from said separated third color source and modulating said light with image information to provide a third image beam of said third color; and means for combining said first, second, and third image beams to provide a multi-colored image beam, wherein said means for combining comprises: a first filter which passes a first one of said image beams and reflects a second one of said image beams; and a second filter which reflects said first and second ones of said image beams and passes a third one of said image beams, wherein none of said first, second or third color of light impinge upon more than three filters.
Claim 4
Dependent Claim
293 words
An optical transmission system comprising: a light source for providing a first, a second and a third color of light; a first means for passing in a first direction said second and third colors of light while passing in a second direction said first color of light as a separated first color source, said first means comprising a filter which passes said first color and reflects said second and third colors in a single direction; a second means for passing in a first direction said second color of light as a separated second color source while passing in a second direction said third color of light as a separated third color source; a first image light valve means for receiving light from said separated first color source and modulating said light with image information to provide a first image beam of said first color; a second image light valve means for receiving light from said separated second color source and modulating said light with image information to provide a second image beam of said second color; a third image light valve means for receiving light from said separated third color source and modulating said light with image information to provide a third image beam of said third color; and means for combining said first, second, and third image beams to provide a multi-colored image beam, wherein said means for combining comprises: a first filter which passes a first one of said image beams and reflects a second one of said image beams; and a second filter which reflects said first and second ones of said image beams and passes a third one of said image beams, wherein none of said first, second or third color of light impinge upon more than three filters.
Claim 5
Dependent Claim
17 words
A system as in claim 1 or 2 wherein said light source comprises a white light source.
Claim 6
Dependent Claim
18 words
A system as in claim 1 or 2 wherein said light source comprises a source of collimated light.
Claim 7
Dependent Claim
18 words
A system as in claim 1 or 2 which further comprises means for focusing said multi-colored image beam.
Claim 8
Dependent Claim
18 words
A system as in claim 1 or 2 which further comprises means for focusing said multi-colored image beam.
Claim 9
Dependent Claim
34 words
A system as in claim 1 or 2 wherein one or more of said first, second, and third image light valve means comprise liquid crystal panels capable of modulating said light with image information.
Claim 10
Dependent Claim
21 words
A system as in claim 1 or 2 wherein a green color beam is not passed through any of said filters.
Claim 11
Dependent Claim
108 words
A color separation and recombination apparatus for color projection display systems comprising: means for separating an input light beam into a plurality of color component light beams having a plurality of separate beam paths; a plurality of image light valves disposed, one each, in said plurality of beam paths, said image light valves modulating said color component light beams with image information; means for combining the color component light beams to produce the output light beam; and an optical path for each color component light beam defined by the means for separating and means for combining such that each color component light beam travels an equal optical path.
Claim 12
Dependent Claim
108 words
A color separation and recombination apparatus for color projection display systems comprising: means for separating an input light beam into a plurality of color component light beams having a plurality of separate beam paths; a plurality of image light valves disposed, one each, in said plurality of beam paths, said image light valves modulating said color component light beams with image information; means for combining the color component light beams to produce the output light beam; and an optical path for each color component light beam defined by the means for separating and means for combining such that each color component light beam travels an equal optical path.
Claim 13
Dependent Claim
26 words
An apparatus as in claim 9 wherein said image light valves each comprise a liquid crystal panel capable of modulating said light beams with image information.
Claim 14
Dependent Claim
19 words
An apparatus as in claim 9 which further comprises a white light source for providing said input light beam.
Claim 15
Dependent Claim
16 words
An apparatus as in claim 4 wherein said light source comprises a source of collimated light.
Claim 16
Dependent Claim
14 words
An apparatus as in claim 9 wherein said means for separating comprise dichroic beamsplitters.
Claim 17
Dependent Claim
14 words
An apparatus as in claim 9 wherein said means for combining comprise dichroic beamsplitters.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-10-15 | 1994-04-16 | 1994-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-15 | 1998-04-16 | 1998-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-15 | 2002-04-16 | 2002-10-16 | $7700.00 | Window Closed / Lapsed |