Patent US5438443A successfully refreshed from Google Patents.
US5438443A
Expired / Lapsed
US
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Liquid crystal device
Assignee: Canon Inc
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Filing: 1994-08-23
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Granted: 1995-08-01
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Expires: 2014-08-23
Abstract
Abstract A liquid crystal device comprising a pair of parallel base plates and a ferroelectric liquid crystal disposed between the base plates. One of the pair of parallel base plates is provided with a plurality of stepwise elevations disposed in the form of stripes, and has been implemented with a uniaxial orientation treatment in a direction parallel to the edges of the stepwise elevations. The stepwise elevation may be formed by a transparent electrode alone or in combination with an alignment control film disposed thereon. Because of the above features, alignment defects liable to develop from the edges of the elevations are removed.
Inventors
- 👤 Osamu Taniguchi
- 👤 Shinjiro Okada
- 👤 Yutaka Inaba
- 👤 Hitoshi Shindo
- 👤 Hirofumi Shibata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:41
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1337; G02F1/137; G02F1/139; G02F1/141; G02F1/13378; G02F1/133784; G02F1/1339; G02F1/13394; G02F1/1343; G02F1/134309; G02F1/134336
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
95 words
A liquid crystal device, comprising: a pair of substrates each having thereon a plurality of stripe-shaped transparent electrodes having a thickness of 800-3,000 Å, said electrodes intersecting each other with a space therebetween, one of the substrates being provided with a uniaxial orientation treatment parallel to the stripe-shaped transparent electrodes thereon, and the other substrate being free from a uniaxial orientation treatment; and a chiral smectic liquid crystal disposed in the space between said transparent electrodes; said liquid crystal further comprising means for providing prior to display driving an AC-voltage sufficient to increase display contrast.
Claim 2
Dependent Claim
95 words
A liquid crystal device, comprising: a pair of substrates each having thereon a plurality of stripe-shaped transparent electrodes having a thickness of 800-3,000 Å, said electrodes intersecting each other with a space therebetween, one of the substrates being provided with a uniaxial orientation treatment parallel to the stripe-shaped transparent electrodes thereon, and the other substrate being free from a uniaxial orientation treatment; and a chiral smectic liquid crystal disposed in the space between said transparent electrodes; said liquid crystal further comprising means for providing prior to display driving an AC-voltage sufficient to increase display contrast.
Claim 3
Dependent Claim
16 words
A liquid crystal device according to claim 1, wherein said uniaxial orientation treatment is rubbing treatment.
Claim 4
Dependent Claim
35 words
A liquid crystal device according to claim 1, wherein said pair of substrates are disposed with a spacing therebetween small enough to suppress the formation of a helical structure of the chiral smectic liquid crystal.
Claim 5
Dependent Claim
29 words
A liquid crystal device according to claim 1, wherein said one of the pair of substrates provided with a uniaxial orientation treatment is provided with an alignment control film.
Claim 6
Dependent Claim
62 words
A liquid crystal device according to claim 1, wherein said alignment control film comprises a resin selected from the group consisting of polyvinyl alcohol, polyimide, polyamide-imide, polyester-imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin, photosensitive polyimide, photosensitive polyamide, cyclic rubber type photoresist, phenol novolak type photoresist, and electron beam resists.
Claim 7
Dependent Claim
20 words
A liquid crystal device according to claim 1, further comprising a spacer material within said space between said tramsparent electrodes.
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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) | 1998-07-31 | 1999-01-30 | 1999-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-31 | 2003-01-30 | 2003-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-31 | 2007-01-30 | 2007-08-01 | $7700.00 | Window Closed / Lapsed |