Patent ID: 6919982

Claim:
An optical path deflecting element, comprising: a pair of transparent substrates being arranged to face each other; transparent electrode films being provided on said substrates, said transparent electrode films to which a voltage having an inverse polarity is selectively applied; an alignment layer being provided in inner sides of said substrates; and a liquid crystal layer being formed of a chiral smectic C phase between said substrates via said alignment layer, said liquid crystal layer being homogeneously aligned by said alignment layer, wherein said substrates are arranged such that said substrates have a slope angle between said substrates so as to form a slope region where said liquid crystal layer is formed, said liquid crystal layer is formed by homogeneously aligning liquid crystal therein in a single-stable condition where a stable condition direction and an unstable condition direction are in an identical plane in said slope region, said stable condition direction and said unstable condition direction alternate in accordance with a polarity of a voltage applied between said transparent electrode films, and said liquid crystal layer is formed of a phase-transition liquid crystal material that does not pass through a smectic A phase.