Asymmetric switching of antiferroelectric liquid-crystal cells

Antiferroelectric liquid-crystal cells usually show symmetric electro-optic switching response from the antiferroelectric state to two opposite ferroelectric states. Intermediate transmission levels (analog gray scale) can be stabilized, applying a constant dc bias voltage after switching. Modifying the manufacturing process and using narrow dynamic-range antiferroelectric materials, a fully asymmetric response has been achieved. This asymmetric switching allows the antiferroelectric cell to be driven as a ferroelectric cell, reducing or eliminating the bias voltage, and ultimately leading to analog optical multistability, i.e., devices whose optical transmission may be arbitrarily set and maintained without power supply. (C) 2001 American Institute of Physics.