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US4398803A
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Liquid crystal display element
Assignee: Merck Patent GmbH
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Filing: 1981-06-15
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Granted: 1983-08-16
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Expires: 2001-06-15
Abstract
Abstract Liquid crystal display elements based on a twisted nematic cell are almost free from interference colors and show only a very little angular dependence of the contrast, if the product of the layer thickness and the optical anisotropy of the liquid crystalline dielectric has a value of 150 to 600 nanometers.
Inventors
- 👤 Ludwig Pohl
- 👤 Rudolf Eidenschink
- 👤 Fernando Del Pino
- 👤 Georg Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:00
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/08; C09K19/30; C09K19/3001; C09K19/3066; C09K19/3068; G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; C09K19/3003; C09K19/32; C09K19/321; G02F1/137; G02F1/139; G02F1/1396; C09K2323/00
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
37 words
In a liquid crystal display element based on a twisted nematic cell the improvement wherein the product of the layer thickness and the optical anisotropy of the liquid-crystalline dielectric has a value of 150 to 600 nm.
Claim 2
Dependent Claim
37 words
In a liquid crystal display element based on a twisted nematic cell the improvement wherein the product of the layer thickness and the optical anisotropy of the liquid-crystalline dielectric has a value of 150 to 600 nm.
Claim 3
Dependent Claim
19 words
A liquid crystal display element according to claim 1, wherein the layer thickness of the dielectric is 3-10 μm.
Claim 4
Dependent Claim
18 words
A liquid crystal display element according to claim 1, wherein the optical anisotropy of the dielectric is 0.03-0.12.
Claim 5
Dependent Claim
25 words
A liquid crystal display element of claim 1, wherein the layer thickness of the liquid-crystalline dielectric is 3-10 μm and the optical anisotropy is 0.03-0.12.
Claim 6
Dependent Claim
16 words
A liquid crystal display cell of claim 1 wherein said product is 350 to 450 nm.
Claim 7
Dependent Claim
22 words
A liquid crystal display cell of claim 4 wherein the dielectric layer thickness is 6-7 μm and the optical anisotropy is 0.05-0.10.
Claim 8
Dependent Claim
64 words
A liquid crystal display element of claim 1, wherein the liquid-crystalline dielectric contains at least 50% by weight of one or more liquid-crystalline compounds from the classes of cyclohexylcyclohexanes; benzoic acid cyclohexyl, bicyclohexyl or cyclohexylphenyl esters; cyclohexane-carboxylic acid phenyl, cyclohexylphenyl, bicyclohexyl or cyclohexyl esters; phenylcyclohexanes; cyclohexylbiphenyls; 4,4'-dicyclohexylbiphenyls; cyclohexylbenzoic acid phenyl or cyclohexyl esters; cyclohexylcyclohexane-carboxylic acid phenyl or cyclohexyl esters; phenyl- or cyclohexyl-1,3-dioxanes; or phenylbicyclo[2.2.2]octanes.
Claim 9
Dependent Claim
25 words
A liquid crystal display cell of claim 4 wherein the layer thickness of the liquid-crystalline dielectric is 3-10 μm and the optical anisotropy is 0.03-0.12.
Claim 10
Dependent Claim
19 words
A liquid crystal display element according to claim 1, wherein the layer thickness of the dielectric is 5-8 μm.
Claim 11
Dependent Claim
18 words
A liquid crystal display element according to claim 1, wherein the optical anisotropy of the dielectric is 0.05-0.10.
Claim 12
Independent Claim
67 words
A method of operating a liquid crystal display element based on a twisted nematic cell so that it possesses a lower degree of interference colors and a lower dependence of contrast on viewing angle, comprising, operating the twisted nematic cell element with a dielectric whose layer thickness and optical anisotropy are such that the product of layer thickness and optical anisotropy has a value of 150-600 nm.
Claim 13
Independent Claim
67 words
A method of operating a liquid crystal display element based on a twisted nematic cell so that it possesses a lower degree of interference colors and a lower dependence of contrast on viewing angle, comprising, operating the twisted nematic cell element with a dielectric whose layer thickness and optical anisotropy are such that the product of layer thickness and optical anisotropy has a value of 150-600 nm.
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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) | 1986-08-15 | 1987-02-14 | 1987-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-15 | 1991-02-14 | 1991-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-15 | 1995-02-14 | 1995-08-16 | $7700.00 | Window Closed / Lapsed |