A NEW METHOD FOR MEASURING THE AZIMUTHAL ANCHORING ENERGY OF A NEMATIC LIQUID-CRYSTAL

We have proposed a new optical method for measuring the twist angle of twisted nematic cells, and the method has been applied to obtain the azimuthal anchoring energy for a nematic liquid crystal. The method is based on a modulation in the polarization state of an incident probin g laser beam to the sample cells, and the resulting transmitted intens ity of the beam is theoretically analyzed through the 2 x 2 Jones matr ix method. The obtained anchoring energy for the azimuthal distortion is about 1.5 x 10(-5) J/m2 for a polyvinylalcohol alignment film; whic h is about two orders of magnitude lower than that for the correspondi ng polar anchoring energy.