Pretilt Control of a Nematic Liquid Crystal on a Selectively Patterned Homeotropic Layer Over a Homogeneous Layer

Abstract

We demonstrated the precise control of the pretilt of a nematic liquid crystal (NLC) on a selectively patterned homeotropic layer over a homogeneous alignment layer through a single photolithography process. Depending on the surface modulation parameters such as the periodicity and the relative dimension between two different patterns, the inhomogeneous substrate with periodic homeotropic and homogeneous patterns produces the pretilt angle of the NLC from zero to several tens degrees. Two different, homogeneous and homeotropic aligning forces for the NLC at the substrate are transferred into the bulk from the surface and result in an intermediate state of the pretilt depending on the surface modulation parameters.