Director Reorientation Dynamics in Chevron Ferroelectric Liquid Crystal Cells

摘要

We present sample numerical solutions of the equation of motion that governs thedynamics of molecular orientation in ferroelectric liquid crystal cells with chevron layer structure. We show that the chevron structure significantly influences the director field, the chevron interface providing surface stabilization on a plane interior to the FLC layer. Assuming non-polar nematic-like elasticity in the vicinity of the chevron interface, we have modelled the effects of applied field on cells with purely non-polar cell boundary interactions that have uniform director orientation at zero field, and on cells in which the cell walls are strongly polar and the zero-field states are splayed. The simulations wtih strongly polar surfaces give bistable operation with the two states having fixed orientations at the FLC-solid surfaces, different orientation of P at the chevron interface, and P splayed in either the upper or lower portion of the cell. A monostable state can arise when the chevron interface is asymmetric, i.e.,located away from the middle of the cell. Experimental results on asymmetric chevron cells qualitatively confirm the calculated switching scenario. (js)