The Studies Of Polymer Stabilized Cholesteric Liquid Crystals Display

NW/NB--PSCTLC has been prepared by doping a sma11 amount ofdiacry1ate monomer in cho1esteric 1 iquid crysta1 s. E1ectroopt i cproperties of NW/NB--PSCTLC has been systematica11y studied andoptimized on the basi 5 of investigation of morpho1ogy and a1ignmentof po1ymer network formed in 1 iqui d crysta1 s. The hysteresi s effects,whi ch strong1y deteri orate gray--sca1 e capac ity and mu1t ip1exing ofPSCTLC, were significant1y improved. The driving vo1tage of PSCTLCwas significant1y reduced to match with addressing TFT and drivingIC.First, the morpho1ogy and texture of po1ymer networks formedin 1 iquid crysta1s were studied by using po1arized microscope andSEM. Effects of curing temperature and UV intens1ty on po1ymernetwork were a1 so investi gated.0n the base of ana1ysis of the process textlure transition ofcho1esteric 1iquid crysta1s, I studied e1ectrooDtic properties ofNW--PSCTLC systemat1ca11y. The structure of po1ymer networks wasoptimized in theory as we1l as in experiment. The hysteresis effectswere improved satisfactori1y whi1e devices kept good contrastperformance. The saturation vo1tage was reduced to about 5 vo1ts byoptlmizing of d/P of devices. A method for quantlfied eva1uating thegray sca1es of NW--PSCTLC correct1y was given in thi s di ssertation.Using thi s method the maximum gray sca1es of devices with hysteresi scan be ca1cu1ated eas i1y. A NW--PSCTLC dynami c digi ta1 di sp1ay samp1edriven with duty of 1/8 has been prepared for the first time in China.During the study of NB--PSCTLC, A fire--watching device wasinvented on the basis of dependence of transmittance at off stateon wave1ength of NB--PSCTLC and cooperated with CCD camera.The mechanism coursing hysteresis effect in NB--PSCTLC wasana1yzed in the 1ast ehapter of this dissertation. A mu1ti--domainmode1, which explained the effects of po1ymer, network on hysteresiswe11. The hysteresis width was enhanced by optimi zing of fabricatingconditions. Stab1e' bi stabi1ity can be rea1ized under very 1owbias--vo1tages with thin ce11s of 7op. A bias driving--scheme wasi11ustrated. NB--PSCTLC can be used to make high definition disp1ayon a passive matrix.