Patent ID: 8963903
Filing Date: 2015-02-24
Classification: G09G

Abstract:
1. An image display device having a memory property comprising: a display section having a first substrate in which pixel electrodes are formed, a second substrate in which a facing electrode is formed, and an electrophoretic layer having a thickness “L” and being interposed between said first substrate and second substrate and containing electrophoretic particles in a manner to enable an electrophoresis in said electrophoretic layer; and a voltage applying unit to sequentially apply, at a time of screen renewal, a plurality of specified voltage driving waveforms to said electrophoretic particles existing between said pixel electrodes and said facing electrode, during a predetermined period of time, to renew a display state of said display section from a previous screen, through a single or a plurality of intermediate transitions, to a next screen, wherein said electrophoretic particles comprise a plurality of kinds of charged particles having colors being different from each other and threshold voltages to initiate the electrophoresis being different from each other, wherein said voltage applying unit, by changing, at the time of screen renewal, a relative color density of each kind of charged particle to a relative color density for renewal, in order of a decreasing threshold voltage of the charged particles, finally renews a screen to a next screen having a desired density, wherein the predetermined period of time, during which said specified voltage driving waveforms are sequentially applied, comprises a plurality of voltage applying periods associated with the plurality of kinds of charged particles in a one-to-one correspondence, and wherein, in each voltage applying period, said voltage applying unit applies a specified voltage driving waveform including |driving voltage| and/or 0V to cause an electrophoresis of a corresponding kind of charged particle to move at a predetermined location at a distance “L wherein said plurality of voltage applying periods is made up of a plurality of sub-frame group periods, and wherein, in each sub-frame group period, said voltage applying unit applies ‘driving voltage’ and/or 0V for a predetermined number of sub-frames to cause an electrophoresis of a corresponding kind of charged particle to move at a predetermined location at distance “L