A ferroelectric liquid crystal device having a pair of substrates each provided with voltage applying means, an orientation control layer formed on at least one of the substrates, and a layer of ferroelectric liquid crystal composition disposed between the pair of substrates, the ferroelectric liquid crystal composition comprising at least one compound (a) having an optically active group of the formula (I): ##STR1## at least one compound (b) which is reverse to the compound (a) in the direction of a helical pitch induced in a nematic phase and at least one liquid crystal compound (c) exhibiting a smectic C phase, the liquid crystal composition exhibiting at least a smectic C phase, smectic A phase and nematic phase.
一种
铁电液晶器件,具有一对基板,每个基板都提供电压施加手段,至少在其中一块基板上形成取向控制层,以及放置在基板对之间的
铁电液晶组成层,所述
铁电液晶组成层包括至少一种具有光学活性基团的化合物(a),其式为(I):##STR1## 至少一种化合物(b),其方向与在向列相中诱导螺旋间距的化合物(a)相反,并且至少一种表现为液晶C相的液晶化合物(c),所述液晶组成物至少表现为液晶C相,液晶A相和向列相。