Development of Micro-Actuators Driven by Liquid Crystals (2nd Report, Effect of Various Parameters)

Abstract

As a purpose of developing liquid crystalline micro-actuators, transient behaviors of a nematic liquid crystal between two parallel plates are computed with various parameters such as applied voltage, gap of the plates, and twist and tilt angles. When the twist angle is 0 deg, the induced flow is planar, and when the twist angle is not 0 deg, on the other hand, the flow has an out of plane component. With increasing the applied voltage, the shear stress acting on the plate, the velocity, and the flow rate are increased and the response is improved. The effect of the gap of the plates is large ; when the gap is reduced to 5 μm, for example, the response is so high that the physical quantities become maxima within a couple of milliseconds. However, if the electric field intensity is kept constant, the effect of the gap is negligible. The tilt angle has comparatively little effect. We can develop micro-actuators with arbitrary characteristics by controlling properly applied voltage, size of actuators, and anchoring conditions.