An orthogonal coupling between liquid crystal layer polarization and externally applied electric field by an SSD liquid crystal

Abstract

TE-mode optical switching by a liquid crystal device attracts interests both its application and scientific principle. Optical axis switching of the liquid crystal molecules perpendicular to the incident light provides TE-mode switching, which enables phase only switching without changing light throughput amplitude. A vertically applied electric filed to a planar aligned liquid crystal layer gives freedom to a liquid crystal panel configuration design. Such a TE-mode optical switching requires orthogonal driving torque of a liquid crystal molecules by vertically applied electric field. A typical dielectric driving torque does not provide such an orthogonal driving. A conceivable orthogonal driving torque is provided by quadrupole momentum. Liquid crystal layer's parallel direction of polarization to the substrates may respond to the vertically applied electric field when the liquid crystal layer shows some quadrupole moment. This investigation tries influence of polarization direction of the liquid crystal layer originated from surface pre-tilt angle as well as its influence on electro-optical behavior.