Study of Twisted Optically Compensated Bend Cell Using Patterned Alignment

We have investigated a new liquid crystal cell based on a nonchiral-doped optically compensated bend (OCB) mode. The average pretilt angle of this cell was higher than that of a conventional OCB cell; when undisturbed, the twist-to-splay energy barrier induced by topological differences remained in a twist state. We have called this twisted cell a twisted optically compensated bend (TOCB) cell. The TOCB cell does not require any warm-up time or warm-up voltage in electrical driving, and the response time of the TOCB cell was as fast as that of a conventional OCB cell. In this study, the TOCB cell was made using a polymer network pattern with high-pretilt-angle alignment, called a patterned-TOCB cell. The patterned-TOCB cell arose from the irradiation of UV light through a photomask and onto a pi cell, which was filled with nematic liquid crystal (NLC) and UV-curable polymer mixture upon a curing voltage being applied to it.