High Speed Addressing of a 0°–360° Bistable Twisted Nematic Liquid Crystal Display

In this letter we report the results of an investigation on the dynamics and optics of a twist bistable liquid crystal display. For the first time, the parameters required for high speed addressing of a 0°–360° bistable device are presented. The display consists of a chiral-doped nematic liquid crystal layer with a nominal surface pretilt. The characteristics of the drive waveform allows selection between two optically distinct twist states of 0° and 360°. Optimizing the ratio of cell thickness to inherent pitch and waveform parameters leads to line selection times, for a multiplexed display, of <100 µs; in contrast with typical nematic bistable displays that require times of ∼10 ms. Full optical response can be achieved in times on the order of 15 ms.