Patent EP0303898A1 successfully refreshed from Google Patents.
EP0303898A1
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Projection-type color display device
Assignee: Seiko Epson Corp
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Filing: 1988-08-03
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Granted: —
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Expires: 2008-08-03
Abstract
Abstract In a projection-type color display device utilizing a plurality of liquid crystal light valves for controlling a corresponding plurality of colored light beams and producing respective color images which are then optically synthesized and projected onto a screen, different types of a liquid crystal light valve are used for forming those color images which undergo an even number of reflections during the optical synthesis on the one hand and those for forming color images which undergo an odd number of reflections during the optical synthesis on the other hand. The two types of liquid crystal light valves are different in a way that an optical arrangment of one type has a mirror-inverted like symmetric relation with respect to that of the other type.
Inventors
- 👤 Shuji Aruga
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 14:43
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/3105; G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133509; G02F1/133512; G02F1/1337
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
120 words
A projection-type color display device comprising liquid crystal light valves for controlling a plurality of colored light beams and producing respective color images, an optical synthesizing system (407) for optically synthesizing said color images, and a projection lens system (410) for projecting the synthesized images onto a screen, characterized in that an optical arrangement of each liquid crystal light valve forming a color image which is guided to said projection lens system (410) through an even number of reflections and the corresponding optical arrangement of each liquid crystal light valve for forming a color image which is guided to the projection lens system through an odd number of reflections have a mirror-inverted like symmetric relation with respect to each other.
Claim 2
Dependent Claim
120 words
A projection-type color display device comprising liquid crystal light valves for controlling a plurality of colored light beams and producing respective color images, an optical synthesizing system (407) for optically synthesizing said color images, and a projection lens system (410) for projecting the synthesized images onto a screen, characterized in that an optical arrangement of each liquid crystal light valve forming a color image which is guided to said projection lens system (410) through an even number of reflections and the corresponding optical arrangement of each liquid crystal light valve for forming a color image which is guided to the projection lens system through an odd number of reflections have a mirror-inverted like symmetric relation with respect to each other.
Claim 3
Dependent Claim
23 words
A display device according to claim 1, wherein the optical arrangement of said liquid crystal light valves is the liquid crystal aligning distribution.
Claim 4
Dependent Claim
39 words
A display device according to claim 1, wherein the optical arrangement of said liquid crystal light valves is the form of a unit pattern (901, 1001) of a light shield layer (101) formed in the liquid crystal light valve.
Claim 5
Dependent Claim
44 words
A display device according to claim 1, wherein the form of the unit pattern (1201) of a light shield layer (101) of the liquid crystal light valve is axially symmetric with respect to a center axis in the vertical direction of the unit pattern.
Claim 6
Dependent Claim
33 words
A display device according to claim 1, wherein the optical arrangement is the arrangement of switching elements (102) in the liquid crystal light valves for controlling the photoelectric effect of the liquid crystal.
Claim 7
Dependent Claim
57 words
A display device according to claim 1, wherein the optical arrangement is the liquid crystal aligning distribution, the form of a unit pattern of a light shield layer formed in the liquid crystal light valve, and the arrangement of switching elements formed in the liquid crystal light valves for controlling the photoelectric effect of the liquid crystal.
Claim 8
Dependent Claim
52 words
A display device according to claim 1, wherein the optical arrangement is the form of a unit pattern of a light shield layer formed in the liquid crystal light valve, and the arrangement of switching elements formed in the liquid crystal light valves for controlling the photoelectric effect of the liquid crystal.
References Cited (Backward Citations)
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