Thin Ferroelectric Liquid Crystal Cells with Surface-Induced Alignment: Optical Characterization and Electro-Optic Performance

Abstract

Different surface treatments commonly used for nematics have been tested for alignment effect on ferroelectric smectic C* liquid crystals. Thin samples of thickness around 2 μm are used in order to elastically unwind the helix present in the chiral smectic materials. Electro-optic measurements are made as a function of temperature and the viscosities are deduced. Response times and frequency cut-offs are presented for four different ferroelectric compounds. For some conditions bistability is observed. Different methods for obtaining good alignment are discussed in view of the reported observations.