EP0179592A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Ferroelectric liquid crystal display cells
Assignee: ITT Inc
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Filing: 1985-10-08
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Granted: —
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Expires: 2005-10-08
Abstract
Abstract A bistable ferroelectric liquid crystal smectic I* or smectic F* display cell has a liquid crystal layer confined between opposed electrode plates (14, 15). The inward facing surfaces are heated to provide planar alignment of the adjacent liquid crystal molecules in the same direction at each of the two surfaces. the plates serve to define a liquid crystal layer in the range 4 to 40 microns but which still permits bistable operation.
Inventors
- 👤 William Alden Crossland
- 👤 Anthony Bernard Davey
- 👤 Matthew Francis Bone
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 00:40
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/08; C09K19/10; C09K19/20; C09K19/2007; C09K19/2021; C09K19/42; C09K19/46; G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/139; G02F1/141
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
77 words
A ferroelectric liquid crystal display cell exhibiting bistability of operation, characterised in that it has a smectic I * or F * phase liquid crystal layer confined between opposed electrode plates (14, 15) whose inward facing surfaces have been treated to promote planar alignment of the adjacent liquid crystal molecules in the same direction at each of the two surfaces, which plates serve to define a liquid crystal layer in the range from 4 to 40 microns.
Claim 2
Dependent Claim
77 words
A ferroelectric liquid crystal display cell exhibiting bistability of operation, characterised in that it has a smectic I * or F * phase liquid crystal layer confined between opposed electrode plates (14, 15) whose inward facing surfaces have been treated to promote planar alignment of the adjacent liquid crystal molecules in the same direction at each of the two surfaces, which plates serve to define a liquid crystal layer in the range from 4 to 40 microns.
Claim 3
Dependent Claim
24 words
A ferroelectric liquid crystal display cell as claimed in claim 1, characterised in that the liquid crystal layer thickness is less than 20 microns.
Claim 4
Dependent Claim
26 words
A ferroelectric liquid crystal display cell as claimed in claim 1 or 2, characterised in that a pleochroic dye is dispersed in the liquid crystal layer.
Claim 5
Dependent Claim
53 words
A ferroelectric liquid crystal display cell as claimed in any one of the preceding claims, characterised in that the plates (14, 15) are formed by layers provided on facing surfaces of two transparent sheets spaced apart to contain and define the thickness of the liquid crystal layer retained therebetween by a perimeter seal.
Claim 6
Dependent Claim
36 words
A ferroelectric liquid crystal display cell as claimed in claim 4, characterised in that the spacing between the sheets and the thickness of the liquid crystal layer are defined by the thickness of the perimeter seal.
Claim 7
Dependent Claim
36 words
A ferroelectric liquid crystal display cell as claimed in claim 4 or 5, characterised in that each of the electrode layers are covered within the display area defined by the perimeter seal with a polymer layer.
Claim 8
Dependent Claim
28 words
A ferroelectric liquid crystal display cell as claimed in any one of the preceding claims, characterised in that the electrode plates comprise a layer of indium tin oxide.
Claim 9
Dependent Claim
28 words
A ferroelectric liquid crystal display cell as claimed in any one of the preceding claims, characterised in that the liquid crystal layer is formed by the chiral ester:-
Claim 10
Dependent Claim
37 words
A ferroelectric liquid crystal display cell as claimed in any one of claims 1 to 7, characterised in that the liquid crystal layer is formed by a non-chiral (racemic) material including 6 wt % of chiral ester.
Claim 11
Dependent Claim
43 words
A ferroelectric liquid crystal display cell as claimed in any one of claims 1 to 7, characterised in that the lqiuid crystal layer contains 20.8 wt % HEPTOBPD (bis-4'-n-heptyloxybenzylidene)-1, 4-phenylenediamine), 79.2 wt % TBBA (terephthalylidene-bis-n-butyl aniline), and 6.1 wt % chiral ester dopant.
References Cited (Backward Citations)
No citation records indexed.
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