Stabilization of Long-Pitch Supertwisted Nematic Structures

Stabilized reverse twisted nematic liquid crystal devices (RTN-LCDs) were fabricated using formation of a polymer matrix under UV irradiation with an applied voltage (sustain voltage) in the vicinity alignment layers. In absence voltage, non-stabilized RTN structure gradually returns to splay twist structure. The sustain was decreased increase temperature. A stabilized long-pitch supertwisted (LPSTN) could also be formed during stabilization process much lower at temperature near clearing point. chiral pitch for LPSTN is longer than that typical STN LPSTN-LCDs similar RTN-LCDs show large reduction both threshold and saturation compared those TN-LCDs consisted same LC materials. Furthermore, notable feature change TN when high applied. black state can realized due from unlike mode crossed nicols condition. contrast STN-LCDs retain their color retardation because states are considered topologically equivalent.