Global Patent Index - EP 0957394 A1

EP 0957394 A1 19991117 - Driving method and apparatus for liquid crystal display device

Title (en)

Driving method and apparatus for liquid crystal display device

Title (de)

Verfahren und Gerät zum Steuern einer Flüssigkristallanzeigevorrichtung

Title (fr)

Méthode et appareil de commande d'un dispositif d'affichage à cristaux liquides

Publication

EP 0957394 A1 19991117 (EN)

Application

EP 99109558 A 19990512

Priority

JP 13201298 A 19980514

Abstract (en)

A technique is described for driving a liquid crystal display device having a liquid crystal layer exhibiting a cholesteric phase and switchable between a planar state and a focal conic state according to the magnitude of an applied voltage. The technique comprises the steps of: in a first period, simultaneously applying a voltage by which a plurality of pixels arranged in a matrix array are reset to the focal conic state; in a second period after the first period, sequentially applying voltages corresponding to image data to the pixels, thereby updating the display contents of the pixels; and in a third period after the second period, retaining the display state by utilizing memory characteristics of the liquid crystal. <IMAGE>

IPC 1-7

G02F 1/137; G09G 3/36

IPC 8 full level

G02F 1/133 (2006.01); G09G 3/36 (2006.01); G09G 3/20 (2006.01)

CPC (source: EP)

G09G 3/3629 (2013.01); G09G 3/2014 (2013.01); G09G 3/3685 (2013.01); G09G 2300/0486 (2013.01); G09G 2310/027 (2013.01); G09G 2310/061 (2013.01); G09G 2320/0209 (2013.01)

Citation (search report)

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0957394 A1 19991117; JP 3713954 B2 20051109; JP H11326871 A 19991126

DOCDB simple family (application)

EP 99109558 A 19990512; JP 13201298 A 19980514