US4896947A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal display cell
Assignee: Rolic Technologies Ltd
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Filing: 1989-06-14
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Granted: 1990-01-30
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Expires: 2009-06-14
Abstract
Abstract A liquid crystal display (LCD) cell comprising a twist nematic liquid crystal disposed between two electrode plates and polarizers and having a positive dielectric anisotropy. The optical path difference DELTA n.d is 0.2 to 0.7 mu m. The absolute value of the twist angle phi can be between 10 DEG and 80 DEG , the angle psi between the polarizers can be between 80 DEG and 110 DEG and the angle theta between the surface orientation direction and the polarization direction on the screen on the light incidence side can be between -10 DEG and 60 DEG , preferably so that the polarizers are symmetrical of the nematic directors.
Inventors
- 👤 Frans Leenhouts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:29
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/139; G02F1/1396; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133528; G02F1/133531
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
124 words
A liquid crystal display (LCD) cell, comprising a twisted nematic liquid crystal having a positive dielectric anisotropy, which is disposed between two plates having electrodes and surface orientations, and wherein the plates are disposed between two polarizers, and further including, in combination, a twist angle φ between the nematic directors of the liquid crystal at the respective plates of from about 10° to about 80°; an angle θ between the surface orientation direction and the polarization direction of the plate on the light incidence side of from about -30° to about 60°; an angle ψ between the polarization directions of the two polarizers of from about 80° to about 110°; and an optical path difference Δn.d of from about 0.2 to about 0.7 μm.
Claim 2
Dependent Claim
124 words
A liquid crystal display (LCD) cell, comprising a twisted nematic liquid crystal having a positive dielectric anisotropy, which is disposed between two plates having electrodes and surface orientations, and wherein the plates are disposed between two polarizers, and further including, in combination, a twist angle φ between the nematic directors of the liquid crystal at the respective plates of from about 10° to about 80°; an angle θ between the surface orientation direction and the polarization direction of the plate on the light incidence side of from about -30° to about 60°; an angle ψ between the polarization directions of the two polarizers of from about 80° to about 110°; and an optical path difference Δn.d of from about 0.2 to about 0.7 μm.
Claim 3
Dependent Claim
23 words
The cell according to claim 1, wherein the optical path difference Δn.d is in a range from about 0.3 to about 0.5 μm.
Claim 4
Dependent Claim
21 words
The cell according to claim 1, wherein the twist angle φ is in a range from about 20° to about 60°.
Claim 5
Dependent Claim
21 words
The cell according to claim 1, wherein the twist angle φ is in a range from about 30° to about 50°.
Claim 6
Dependent Claim
24 words
The cell according to claim 1, wherein the angle θ is defined by the condition θ=(90°-φ)/2, the angle ψ between the polarizers being 90°.
Claim 7
Dependent Claim
20 words
The cell according to claim 1, wherein the angle θ is in a range from about 0° to about 60°.
Claim 8
Dependent Claim
20 words
The cell according to claim 1, wherein the angle θ is in a range from about -30° to about 0°.
Claim 9
Dependent Claim
13 words
The cell according to claim 1, wherein the angle ψ is about 90°.
Claim 10
Dependent Claim
124 words
A liquid crystal display (LCD) cell, comprising a twisted nematic liquid crystal having a positive dielectric anisotropy, which is disposed between two plates having electrodes and surface orientations, and wherein the plates are disposed between two polarizers, and further including, in combination, a twist angle φ between the nematic directors of the liquid crystal at the respective plates of from about 30° to about 50°; an angle θ between the surface orientation direction and the polarization direction of the plate on the light incidence side of from about -30° to about 60°; an angle ψ between the polarization directions of the two polarizers of from about 80° to about 110°; and an optical path difference Δn.d of from about 0.2 to about 0.7 μm.
Claim 11
Dependent Claim
124 words
A liquid crystal display (LCD) cell, comprising a twisted nematic liquid crystal having a positive dielectric anisotropy, which is disposed between two plates having electrodes and surface orientations, and wherein the plates are disposed between two polarizers, and further including, in combination, a twist angle φ between the nematic directors of the liquid crystal at the respective plates of from about 30° to about 50°; an angle θ between the surface orientation direction and the polarization direction of the plate on the light incidence side of from about -30° to about 60°; an angle ψ between the polarization directions of the two polarizers of from about 80° to about 110°; and an optical path difference Δn.d of from about 0.2 to about 0.7 μm.
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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) | 1993-01-29 | 1993-07-31 | 1994-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-29 | 1997-07-31 | 1998-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-29 | 2001-07-31 | 2002-01-30 | $7700.00 | Window Closed / Lapsed |