US4867539A
Expired / Lapsed
US
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Ferroelectric liquid crystal devices
Assignee: Nokia Bell Labs
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Filing: 1988-11-23
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Granted: 1989-09-19
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Expires: 2008-11-23
Abstract
Abstract Excellent ordering in ferroelectric liquid crystal devices is obtained by utilizing a material having a smectic C phase and no higher temperature orthogonal smetic phases. Ordering is accomplished by the combination of (1) contacting the liquid crystal material in the smectic C phase with an ordering substance and (2) subjecting the liquid crystal material to a slowly varying electric field.
Inventors
- 👤 John W. Goodby
- 👤 Jayantilal S. Patel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:16
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/139; G02F1/141; C; C09; C09K; C09K19/00; C09K19/02; C09K19/0225; C09K19/04; C09K19/06; C09K19/08; C09K19/10; C09K19/20; C09K19/2007; C09K19/2021; C09K2019/2035
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
92 words
A process for fabricating a ferroelectric liquid crystal device including a liquid crystal material and electrodes suitable for inducing an observable optical change in said liquid crystal material, said process comprising the steps of: (1) contacting said liquid crystal with an ordering substance and (2) applying a slowly varying AC field across said liquid crystal material while said liquid crystal material is in a smectic C phase wherein there is an absence in said liquid crystal material of a smectic A phase at a temperature above that of said smectic C phase.
Claim 2
Dependent Claim
92 words
A process for fabricating a ferroelectric liquid crystal device including a liquid crystal material and electrodes suitable for inducing an observable optical change in said liquid crystal material, said process comprising the steps of: (1) contacting said liquid crystal with an ordering substance and (2) applying a slowly varying AC field across said liquid crystal material while said liquid crystal material is in a smectic C phase wherein there is an absence in said liquid crystal material of a smectic A phase at a temperature above that of said smectic C phase.
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein said liquid crystal material comprises (s)-4-n-decyloxyphenyl 4-(3,7-dimethyloctyloxy)benzoate.
Claim 4
Dependent Claim
21 words
The process of calim 2 wherein said slowly varying field has an average frequency in the range 10 to 100 Hz.
Claim 5
Dependent Claim
21 words
The process of calim 2 wherein said slowly varying field has an average frequency in the range 10 to 100 Hz.
Claim 6
Dependent Claim
13 words
The process of claim 3 wherein said ordering substance comprises a polyester polymer.
Claim 7
Dependent Claim
21 words
The process of claim 1 wherein said slowly varying field has an average frequency in the range 10 to 100 Hz.
Claim 8
Dependent Claim
13 words
The process of claim 1 wherein said ordering substance comprises a polyester polymer.
Claim 9
Dependent Claim
13 words
The process of claim 1 wherein said liquid crystal material comprises (s)-4-n-decyloxyphenyl 4-(3,7-dimethyloctyloxy)benzoate.
Claim 10
Dependent Claim
16 words
The process of claim 1 wherein said electrodes are employed to apply said slowly varying field.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-09-18 | 1993-03-20 | 1993-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-18 | 1997-03-20 | 1997-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-18 | 2001-03-20 | 2001-09-19 | $7700.00 | Window Closed / Lapsed |