Fabrication of vertical alignment in ferroelectric liquid crystals for display application

Abstract

In this study, we focus on vertical alignment ferroelectric liquid crystals (VA-FLCs), because an FLC display with a high contrast ratio is expected. In the VA, although the normal of smectic layers is vertical to the substrate surface, the director of FLC molecules must tilt to the substrate surface at the tilt angle of FLC molecules. Thus, it is usually difficult to obtain a uniform VA in FLCs. We determine the optimum conditions for the fabrication of VA-FLC cells in terms of the tilt angle of FLC molecules, the anchoring strength of the alignment film, and the cell gap. Results indicate that the FLC with a small tilt angle tends to form good VA, which can be obtained by utilizing alignment films with high surface anchoring strengths. Good VA strongly depends on the cell gap.

Effect of rubbing symmetry on polarization distribution in ferroelectric nematic liquid crystal cells

“…The molecular orientation properties of LC materials with macroscopic polarization strongly depend on alignment materials and orientation treatments. [21][22][23][24][25][26] In previous studies, a polarization model for sandwich cells with the rubbing treatment, which is the most common orientation control method, has been presented. 21,[27][28][29][30] These studies have been performed as part of clarifying the mechanism of polarization states and domain formation in cells.…”