The influence of thermodynamic equilibrium state prior to the phase transition on the alignment of ferroelectric liquid crystal

In this experiment, devices of ferroelectric liquid crystal (FLC) were prepared by selecting ZLI-3654 FLC and SE-3140 alignment material. In order to study the influence of thermodynamic equilibrium state before the phase transition on the alignment of FLC, ten sets of experiments were carried out by changing the cooling rate during phase transition and thermodynamic equilibrium state before the phase transition. From experiments, a conclusion that the thermodynamic equilibrium state prior to chiral nematic-smectic A (N * -SmA) phase transition play an important role in realizing a uniform alignment of FLC devices, was obtained by comparing static contrasts of the devices. The static contrast ratio of our samples reached 620 ∶1 and the thermodynamic equilibrium state before N * -SmA phase transition was conducive to the formation of high contrast ratio FLC devices. The conclusion can provides a theoretical and practical guidance for the fabrication of FLC devices with I←→N * ←→SmA←→S * mC←→Cr phase sequence.