MEASUREMENT OF TWIST ANGLE AND SURFACE TORSIONAL ANCHORING STRENGTH IN A NEMATIC LIQUID-CRYSTAL CELL

In this paper a novel method is developed for measuring the twist angl e and surface torsional anchoring strength in nematic liquid crystal ( NLC) cells. This method is based on a technique developed from the Jon es optical propagation matrix. From the measurement, the actual twist angle in NLC cell and the deviation of the LC director on the boundary of the eel from the rubbing direction of the substrate are obtained. A theoretical discussion shows that the surface torsional anchoring st rength has a great influence on the value of the deviation, and hence so it can be calculated.