US4779958A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal device having different natural and induced twists
Assignee: Toshiba Corp
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Filing: 1987-06-19
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Granted: 1988-10-25
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Expires: 2007-06-19
Abstract
Abstract In a liquid crystal device, liquid crystal molecules are twisted at a predetermined angle θ within the range of 180° to 360° between a pair of substances. Molecular alignment films are formed on the inner surfaces of the pair of substrates such that an angle α between the axes of the adjacent liquid crystal molecules falls within the range of 0° to 40°. A liquid crystal composition having a twist abilities falling within the range of θ-(2500/θ)+√α (degrees) to θ-(12500/θ)+√α (degrees) is filled between the substrates, thereby eliminating a memory phenomenon and alignment defects such as reverse twisting alignment defects and at the same time improving multiplexing drive characteristics.
Inventors
- 👤 Yoshinori Kato
- 👤 Kiyoshi Shohara
- 👤 Yoshihiro Kinoshita
- 👤 Shoichi Matsumoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:16
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/139; G02F1/1396; G02F1/1397
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
106 words
A liquid crystal device comprising: a pair of substrates opposite to each other, a liquid crystal composition, having liquid crystal molecules, positioned between said substrates, molecular alignment films respectively formed on inner surfaces of the pair of substrates to twist said liquid crystal molecules at a predetermined angle θ within a range between 180° and 360° between the pair of substrates and to set a pretilt angle α0 formed between adjacent ones of the liquid crystal molecules to be within a range of 0° to 40°, and said liquid crystal composition having a twist ability which falls within a range of θ-(2500/θ)+√α0 (degrees) to θ-(12500/θ)+√α0 (degrees).
Claim 2
Dependent Claim
106 words
A liquid crystal device comprising: a pair of substrates opposite to each other, a liquid crystal composition, having liquid crystal molecules, positioned between said substrates, molecular alignment films respectively formed on inner surfaces of the pair of substrates to twist said liquid crystal molecules at a predetermined angle θ within a range between 180° and 360° between the pair of substrates and to set a pretilt angle α0 formed between adjacent ones of the liquid crystal molecules to be within a range of 0° to 40°, and said liquid crystal composition having a twist ability which falls within a range of θ-(2500/θ)+√α0 (degrees) to θ-(12500/θ)+√α0 (degrees).
Claim 3
Dependent Claim
17 words
The device according to claim 1, wherein the substrates respectively have transparent electrodes on inner surfaces thereof.
Claim 4
Dependent Claim
14 words
The device according to claim 2, wherein the transparent electrodes comprise stripe electrodes, respectively.
Claim 5
Dependent Claim
17 words
The device according to claim 1, wherein the substrates respectively have polarizing plates on outer surfaces thereof.
Claim 6
Dependent Claim
15 words
The device according to claim 1, wherein the molecular alignment films are formed by depositing.
Claim 7
Dependent Claim
16 words
The device according to claim 1, wherein the molecular alignment films are formed by oblique deposition.
Claim 8
Dependent Claim
22 words
The device according to claim 1, wherein the liquid crystal composition is prepared by adding a chiral dopant to the liquid cystal.
Claim 9
Dependent Claim
26 words
The device according to claim 1, wherein the liquid crystal composition ia prepared by adding a chiral dopant and a dichroic dye to a liquid crystal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-10-25 | 1992-04-25 | 1992-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-25 | 1996-04-25 | 1996-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-25 | 2000-04-25 | 2000-10-25 | $7700.00 | Window Closed / Lapsed |