US3625591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal display element
Assignee: International Business Machines Corp
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Filing: 1969-11-10
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Granted: 1971-12-07
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Expires: 1989-11-10
Abstract
Abstract An electro-optical display device employing a cell comprising a nematic liquid between two glass plates whose inner surfaces have been coated with transparent electrodes. Such coated electrodes are rubbed with a cloth or filter paper so that the liquid crystal film becomes oriented along the direction of rubbing. Such film will be homogeneous and strongly birefringent so that when an electric field is applied to the electrodes of the cell and the latter is viewed between crossed polarizers, a marked contrast in light between the quiescent and active states, respectively, of the cell is observed, even in the presence of ambient illumination of the cell.
Inventors
- 👤 Marvin J Freiser
- 👤 Ivan Haller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:04
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/13743; G02F1/1375; C; C09; C09K; C09K2323/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
157 words
An electro-optical display device comprising two parallel transparent members spaced apart a distance of 10-500 microns, transparent electrodes on the facing surfaces of said members, a nematic liquid interposed and filling the space between said electrodes and having all its molecules in their quiescent state, nonelectrically aligneD parallel to such facing surfaces along a given direction in said surfaces, due to said electrodes having rubbed in said given direction, said liquid having a threshold electric field which, when exceeded, causes said liquid to depolarize polarized light passing therethrough, two crossed polarizers located adjacent said transparent members, each polarizer located on the outer surface of its respective transparent member and having a direction of polarization respectively perpendicular and parallel to said given direction, and means for selectively applying an electric field across said liquid through said electrodes that exceeds said threshold electric field, whereby said nematic liquid is switched from its quiescent state to polarize light passing therethrough.
Claim 2
Dependent Claim
157 words
An electro-optical display device comprising two parallel transparent members spaced apart a distance of 10-500 microns, transparent electrodes on the facing surfaces of said members, a nematic liquid interposed and filling the space between said electrodes and having all its molecules in their quiescent state, nonelectrically aligneD parallel to such facing surfaces along a given direction in said surfaces, due to said electrodes having rubbed in said given direction, said liquid having a threshold electric field which, when exceeded, causes said liquid to depolarize polarized light passing therethrough, two crossed polarizers located adjacent said transparent members, each polarizer located on the outer surface of its respective transparent member and having a direction of polarization respectively perpendicular and parallel to said given direction, and means for selectively applying an electric field across said liquid through said electrodes that exceeds said threshold electric field, whereby said nematic liquid is switched from its quiescent state to polarize light passing therethrough.
Claim 3
Dependent Claim
161 words
An electro-optical display device comprising two parallel transparent members spaced apart between 10-500 microns, transparent electrodes on the facing surfaces of said members, a nematic liquid interposed and filling the space between said electrodes and having all its molecules in their quiescent state, nonelectrically aligned parallel to such facing surfaces along a given direction in said surfaces, due to said electrodes having rubbed in said given direction, said liquid having a threshold electric field which, when exceeded, causes said liquid to depolarize polarized light passing therethrough, two crossed polarizers located adjacent said transparent members, each polarizer located on outer surface of its respective transparent member and having a direction of polarization respectively perpendicular and parallel to said given direction, a mirror adjacent one of said polarizers, and means for selectively applying an electric field across said liquid through said electrodes that exceeds said threshold electric field, whereby said nematic liquid is switched from its quiescent state to polarize light passing therethrough.
Claim 4
Dependent Claim
161 words
An electro-optical display device comprising two parallel transparent members spaced apart between 10-500 microns, transparent electrodes on the facing surfaces of said members, a nematic liquid interposed and filling the space between said electrodes and having all its molecules in their quiescent state, nonelectrically aligned parallel to such facing surfaces along a given direction in said surfaces, due to said electrodes having rubbed in said given direction, said liquid having a threshold electric field which, when exceeded, causes said liquid to depolarize polarized light passing therethrough, two crossed polarizers located adjacent said transparent members, each polarizer located on outer surface of its respective transparent member and having a direction of polarization respectively perpendicular and parallel to said given direction, a mirror adjacent one of said polarizers, and means for selectively applying an electric field across said liquid through said electrodes that exceeds said threshold electric field, whereby said nematic liquid is switched from its quiescent state to polarize light passing therethrough.
Claim 5
Dependent Claim
12 words
The electro-optical device of claim 1 wherein said nematic liquid is p-methoxybenzylidene-p-n-butylaniline.
Claim 6
Dependent Claim
12 words
The electro-optical device of claim 2 wherein said nematic liquid is p-methoxybenzylidene-p-n-butylaniline.
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) | 1974-12-06 | 1975-06-07 | 1975-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-06 | 1979-06-07 | 1979-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-06 | 1983-06-07 | 1983-12-07 | $7700.00 | Window Closed / Lapsed |