Electrooptical Switching of Ferroelectric Liquid Crystals in Electrically Distorted Chevron Structure

X-ray diffraction studies on the field induced distortion of the layer structure in ferroelectric liquid crystals are reported. Depending on the liquid crystal materials and alignment layers, electric fields produced reversible or irreversible distortions. Bistable electrooptical switching was observed only in the samples with the irreversibly distorted layer structure. Experimental results on the light transmissions indicated that a bookshelf-like structure was formed in the above bistable sample. It seemed that this structure formation was essential to the bistability of the ferroelectric liquid crystals.