Phase gratings in pretilted homeotropic cholesteric liquid crystal films

Abstract

We studied the fingerprint texture of homeotropic cholesteric liquid crystal (CLC) films. Parallel (360) and antiparallel (180) alignment treatments were adopted for these films such that the molecules at the boundaries had an approximately I pretilt angle to the substrate normal. The experimental results showed that the homeotropic film may be more suitable than the planar-parallel film for use in an electrically controlled phase grating.