US3728007A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflective type liquid crystal display device having improved optical contrast
Assignee: SCM Corp
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Filing: 1971-05-27
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Granted: 1973-04-17
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Expires: 1991-05-27
Abstract
Abstract A high contrast reflective liquid crystal display device is disclosed comprising a transparent plate, a mirror disposed in spaced juxtaposition with the transparent plate, a mesomorphic compound confined between the transparent plate and the mirror, and means for establishing electric fields through selected portions of the mesomorphic compound. Ambient light rays impinging on the mirror are reflected along a first path. A light baffle is included which comprises a member located transverse to the first path and providing good light absorption and specular reflection. Reflected light from the mirror which is incident on the member is re-reflected along a second path to another member providing good light absorption and diffuse reflection. The mirror may be planar or serrated.
Inventors
- 👤 K Myrenne
- 👤 C Hedman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 00:50
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
160 words
An electro-optical display device comprising: a transparent plate (40); a mirror (42) disposed in spaced juxtaposition with said transparent plate; a nematic mesomorphic compound (43) confined between said transparent plate and said mirror; means (FIG. 3) for establishing electric fields through selected portions of said nematic mesomorphic compound; an ambient source of light rays (44 or 85) said light rays impinging on said mirror and being reflected thereby along a first path, and a tip light baffle for intercepting the reflected ambient light rays, comprising a first surface (80) having properties of high light absorption and specular reflection, said first surface being locatEd near the mirror and transverse to said first path, whereby a portion of the reflected ambient light rays are absorbed and the remainder rereflected along a second path, together with a second surface (84) having properties of high light absorption and diffuse reflection, the second surface being located at least along and transverse to the second path.
Claim 2
Dependent Claim
160 words
An electro-optical display device comprising: a transparent plate (40); a mirror (42) disposed in spaced juxtaposition with said transparent plate; a nematic mesomorphic compound (43) confined between said transparent plate and said mirror; means (FIG. 3) for establishing electric fields through selected portions of said nematic mesomorphic compound; an ambient source of light rays (44 or 85) said light rays impinging on said mirror and being reflected thereby along a first path, and a tip light baffle for intercepting the reflected ambient light rays, comprising a first surface (80) having properties of high light absorption and specular reflection, said first surface being locatEd near the mirror and transverse to said first path, whereby a portion of the reflected ambient light rays are absorbed and the remainder rereflected along a second path, together with a second surface (84) having properties of high light absorption and diffuse reflection, the second surface being located at least along and transverse to the second path.
Claim 3
Dependent Claim
98 words
An electro-optical display device in accordance with claim 1 wherein said transparent plate has a substantially planar front surface and a substantially planar rear surface; said nematic mesomorphic compound is confined between said planar rear surface and said mirror; and said mirror comprises a first set of spaced planar mirrors disposed in spaced mutually parallel juxtaposition with said planar rear surface of the plate, said light rays being reflected along a first set of paths by said first set of spaced planar mirrors, and said light baffle being transverse to each path of said first set of paths.
Claim 4
Dependent Claim
83 words
An electro-optical display device in accordance with claim 2 further comprising a second set of spaced mutually parallel planar mirrors interposed between said first set of spaced mutually parallel planar mirrors to form a serrated mirror system, said light rays being reflected by said second set of spaced planar mirrors along a second set of paths angularly disposed with respect to said first set of paths; and wherein said light baffle includes means transverse to each path of said second set of paths.
Claim 5
Dependent Claim
23 words
An electro-optical display device in accordance with claim 1, wherein said first surface comprises a second mirror mounted parallel to said transparent plate.
Claim 6
Dependent Claim
22 words
An electro-optical display device in accordance with claim 4, wherein said second mirror comprises a sheet of glass with a black backing.
Claim 7
Dependent Claim
23 words
An electro-optical display device in accordance with claim 1 wherein said mirror is planar and said light baffle has a black first surface.
Claim 8
Dependent Claim
22 words
An electro-optical display device in accordance with claim 6 wherein said black first surface is a planar surface facing said planar mirror.
Claim 9
Dependent Claim
22 words
An electro-optical display device in accordance with claim 7 wherein said planar mirror and said planar black first surface are substantially parallel.
Claim 10
Dependent Claim
27 words
An electro-optical display device in accordance with claim 8, said second surface comprising black plastic foam disposed adjacent said planar black first surface and said planar mirror.
References Cited (Backward Citations)
US3499112A
Cited
US3592527A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |