Alignment Effects on the Dynamic Scattering Characteristics of an Ester Liquid Crystal

Abstract

The effects of surface alignment are studied on the ac dynamic scattering characteristics of a phenyl benzoate nematic liquid crystal. Seven different alignment modes are used with identical liquid crystal samples by pretreating the conductive glass surfaces to obtain the desired alignments. We find that the threshold voltage (V _th) increases with increasing initial average tilt angle (θ) between the liquid crystal director and the two electrode surfaces. The V _th increases linearly as the cos θ decreases. The surface-perpendicular alignment (θ = 90[ddot]) has almost twice the V _th of the surface-parallel alignment. The dynamic scattering decay times are considerably shorter when θ = 0[ddot] than when θ > 0[ddot]. The scattering versus voltage curves and the microscopic domain patterns are highly dependent upon the initial alignment, even at 1.5 to 2.0 times v _th.