Patent EP0062499A1 successfully refreshed from Google Patents.
EP0062499A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Cell isolation in bistable nematic liquid crystal displays
Assignee: AT&T Inc
•
Filing: 1982-04-01
•
Granted: —
•
Expires: 2002-04-01
Abstract
Abstract In order to prevent drift between the two stable states in the liquid crystal material of a display cell (Fig. 9, V or H) a cell isolation region (N t ) formed from the same liquid crystal material is provided. This cell isolation is provided in one embodiment by a uniformly tilted liquid crystal alignment. The surface of the substrates between which the liquid crystal material is disposed is treated to provide the uniform tilt in regions which surround the bistable volumes of liquid crystal material.
Inventors
- 👤 Julian Cheng
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 09:42
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/13725; G02F1/133; G02F1/1333; G02F1/1337; G02F1/133753; G02F1/139; G02F1/1391; G02F1/133738; G02F1/133742; G02F1/133761
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
138 words
A liquid crystal display comprising a liquid crystal material having orientational directors disposed between first (1) and second (2) substrates, said liquid crystal material being mainly in the nematic mesophase, and the inner surfaces of said substrates being treated so that said orientational directors are aligned in predetermined patterns at said substrate surfaces, which patterns provide substantially bistable cells; CHARACTERIZED IN THAT each of said cells (FIG. 9, V or H) is bounded by a neutral isolation region (N t ), the angle between the orientational director alignments on each side of the boundary (331-334) at one substrate (1) inner surface has a value substantially in the range of 45 degrees to 135 degrees; and there being substantially no discontinuity in orientational director alignments at the boundary at the inner surface of the other (2) of said substrates.
Claim 2
Dependent Claim
138 words
A liquid crystal display comprising a liquid crystal material having orientational directors disposed between first (1) and second (2) substrates, said liquid crystal material being mainly in the nematic mesophase, and the inner surfaces of said substrates being treated so that said orientational directors are aligned in predetermined patterns at said substrate surfaces, which patterns provide substantially bistable cells; CHARACTERIZED IN THAT each of said cells (FIG. 9, V or H) is bounded by a neutral isolation region (N t ), the angle between the orientational director alignments on each side of the boundary (331-334) at one substrate (1) inner surface has a value substantially in the range of 45 degrees to 135 degrees; and there being substantially no discontinuity in orientational director alignments at the boundary at the inner surface of the other (2) of said substrates.
Claim 3
Dependent Claim
21 words
A liquid crystal display in accordance with claim 1 wherein the orientational directors in said neutral isolation region are substantially parallel.
Claim 4
Dependent Claim
33 words
A liquid crystal cell in accordance with claim 2 wherein the orientational directors in said neutral isolation region are aligned at substantially the same angle relative to said first or said second substrate.
Claim 5
Dependent Claim
28 words
A liquid crystal cell in accordance with claim 3 wherein the orientational directors in said bistable volumes are substantially parallel to the orientational directors in said neutral region.
Claim 6
Dependent Claim
28 words
A liquid crystal cell in accordance with claim 3 wherein the orientational directors in said bistable volumes are substantially perpendicular to the orientational directors in said neutral region.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.