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US5227904A
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Ferroelectric liquid crystal device
Assignee: Onanovich Group AG LLC
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Filing: 1991-07-12
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Granted: 1993-07-13
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Expires: 2011-07-12
Abstract
Abstract A ferroelectric liquid crystal device includes a pair of substrates which has electrodes formed in an opposing spatial relation to each other. At least one of the electrodes is optically transparent. A parallel aligned, obliquely evaporated film is formed on each electrode. The paired substrates are sealed to provide a cell. A ferroelectric liquid crystal composition to which an ionic substance having a great mobility is added is placed in the cell to obtain the liquid crystal device. The addition of the ionic substance results in a low switching threshold voltage, a high response speed and good memory reproducibility. When the device is applied with an AC electric field prior to driving, display contrast is significantly improved.
Inventors
- 👤 Jun Nakanowatari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:10
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/52; C09K19/58; C09K19/582; C09K19/02; C09K19/0208; G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/139; G02F1/141; G02F1/133; G02F1/1333; G02F1/1337; G02F1/133734
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
69 words
A ferroelectric liquid crystal device which comprises a pair of substrates having, respectively, electrodes formed in opposing spatial relation to each other, at least one of the electrodes being optically transparent, a parallel aligned, obliquely evaporated film formed on the electrode of the respective substrates, and a ferroelectric liquid crystal composition to which an ionic substance having a great mobility is added and which is confined between the substrates.
Claim 2
Dependent Claim
69 words
A ferroelectric liquid crystal device which comprises a pair of substrates having, respectively, electrodes formed in opposing spatial relation to each other, at least one of the electrodes being optically transparent, a parallel aligned, obliquely evaporated film formed on the electrode of the respective substrates, and a ferroelectric liquid crystal composition to which an ionic substance having a great mobility is added and which is confined between the substrates.
Claim 3
Dependent Claim
28 words
The device according to claim 1, wherein said ionic substance is added in an amount of from 0.01 to 1 wt % of the ferroelectric liquid crystal composition.
Claim 4
Dependent Claim
22 words
The device according to claim 1, wherein said ionic substance has a mobility of not less than 1×10 -6 cm 2 /V·second.
Claim 5
Dependent Claim
18 words
The device according to claim 1, further comprising a surface-modifying functional layer formed on each obliquely evaporated film.
Claim 6
Dependent Claim
16 words
The device according to claim 4, wherein said surface-modifying functional layer is made of a polymer.
Claim 7
Dependent Claim
20 words
The device according to claim 4, wherein said surface-modifying functional layer has a thickness of from 3 to 60 nm.
Claim 8
Dependent Claim
33 words
The device according to claim 1, wherein said obliquely evaporated film is made of a member selected from the group consisting of silicon oxides, metal oxides, silicon nitrides, metal nitrides and mixtures thereof.
Claim 9
Dependent Claim
28 words
The device according to claim 1, further comprising a means for applying an AC electric field between the facing electrodes for a given time prior to display drive.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-07-12 | 1997-01-11 | 1997-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-12 | 2001-01-11 | 2001-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-12 | 2005-01-11 | 2005-07-13 | $7700.00 | Window Closed / Lapsed |