Method of driving ferroelectric liquid crystal element
Abstract
A method of driving a liquid crystal display element in which a switching element is provided for each of pixel electrodes arranged in a matrix manner and a ferroelectric liquid crystal is sandwiched between the pixel electrodes and a counter electrode includes the steps of applying a reset voltage for resetting the entire pixel to a first stable state of the ferroelectric liquid crystal across the pixel electrode and the counter electrode, partially transiting the pixel to a second stable state by a tone signal voltage having a pole opposite to that of the reset voltage, and reversing the pole of the reset voltage every predetermined period. Assuming that a state reverse ratio of the ferroelectric liquid crystal is T(V)% when the tone signal voltage is V, a tone signal voltage V₁ after negative resetting and a corresponding tone signal voltage -V₂ after positive resetting satisfy the following relation: T(V₁) + T(V₂) = 100
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Projected expiry passed 19 March 2011, 15.5 years ago.
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9 members in 5 offices
Priority claims6
| Document | Office | Kind | Date |
|---|---|---|---|
| 7051190 | Japan | – | |
| 7051190 | Japan | A | |
| 7420591 | Japan | – | |
| 7420591 | Japan | A | |
| JP19900070511 | – | – | – |
| JP19910074205 | – | – | – |
Members9
| Document | Office | Kind | |
|---|---|---|---|
| EP0448032A2 | European Patent Office (EPO) | A2 | |
| JPH04218023A | Japan | A | |
| EP0448032A3This record | European Patent Office (EPO) | A3 | |
| US5227900A | United States of America | A | |
| EP0448032B1 | European Patent Office (EPO) | B1 | |
| AT140097T | Austria | T | |
| DE69120564D1 | Germany | D1 | |
| DE69120564T2 | Germany | T2 | |
| JP2805253B2 | Japan | B2 |
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Numbers
- Publication
- 0448032
- Publication, DOCDB
- 0448032
- Publication, EPODOC
- EP0448032
- Application
- 104222
- Application, DOCDB
- 91104222
- Application, EPODOC
- EP19910104222
Titles3
- English
- Method of driving ferroelectric liquid crystal element and ferroelectric liquid crystal display
- German
- Verfahren zur Ansteuerung eines ferroelektrischen Flüssigkristallelementes und ferroelektrische Flüssigkristallanzeige
- French
- Méthode de commande d'un élément à cristal liquide ferroélectrique et affichage à cristaux liquides ferroélectriques
Classification
- CPC, 7
- G09G3/3651
- G09G3/2011
- G09G3/207
- G09G3/3614
- G09G3/367
- G09G2310/0251
- G09G2310/061
- IPC, 4
- G02F1 133
- G09G3 18
- G09G3 20
- G09G3 36
Designated states14
- Contracting states, 14
- Austria
- Belgium
- Switzerland
- Germany
- Denmark
- Spain
- France
- United Kingdom
- Greece
- Italy
- Liechtenstein
- Luxembourg
- Netherlands (Kingdom of the)
- Sweden