| abstract |
An electro-optical device including a chiral smectic C or H liquid crystal disposed between flat plates treated to enforce molecular orientation parallel to the plates. The plates are spaced by a distance sufficiently small to ensure unwinding of the helix typical in a bulk of the material to form two stable states of the orientation field. The liquid crystal is switched between two stable states by reversing the polarity of an externally applied electric field to make a bistable light valve or other electro-optical devices. |