Time Dependent Observation of the Conoscopic Figures of Twisted Liquid Crystal

The conoscopic figures of a twisted p type nematic liquid crystal of about 10 µm thickness are recorded as the function of pulse number of the applied alternating electric field of rectangular wave form. The newly obtained results are as follows; (1) the position of the center of the isogyers, or the direction of optic axis, depends only on the amplitude of the alternating electric field and does not depend on the applied pulse number, (2) the visibility of the isogyers increases with the increase in pulse number without changing position. A possible mechanism of the alignment of liquid crystal molecule is suggested.