Cholesteric liquid crystal display device and method for driving cholesteric liquid crystal display element

• Main Authors: KAMATA TOSHIAKI, KITAOKA MASAKI
• Format: Patent
• Language: English
• Published: 14.09.2005
• Edition: 7
• Subjects: ADVERTISING; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; CRYPTOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; DISPLAY; EDUCATION; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; SEALS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

A method for driving a cholesteric liquid crystal display device which matrix-drives a cholesteric liquid crystal with common electrodes and segment electrodes which cross and oppose to one another. A common electrode driving voltage waveform including a reset waveform, selected waveform, retained waveform, and non-selected waveform is impressed sequentially on the cholesteric liquid crystal device from each common electrode, and an ON waveform and OFF waveform from each segment electrode. The common electrode driving voltage waveform is so formed a period where the same voltage is impressed simultaneously on all the common electrodes is not included within a period from the start of impressing the retained waveform on the first common electrode to the end of impressing the reset waveform on the last common electrode. The segment electrode drive voltage waveform is so formed as to include a period where the same voltage is impressed simultaneously.