High-Tilt, High-P _S , de Vries FLCs for Analog Electro-Optic Phase Modulation

Abstract

Four new de Vries I-A-C* ferroelectric liquid crystal mixtures have been formulated to have high tilt (45°), high polarization, and low smectic layer shrinkage for use in analog electro-optic phase modulators. The mixtures are based on a high-tilt anti-ferroelectric compound which, when combined with other compounds, results in ferroelectric I-A-C* materials. Three of the mixtures include a new germanium-containing liquid crystal compound. X-ray diffraction measurements show layer contraction as small as 7%, while the temperature-dependence of birefringence shows a sharp increase at the A → C* transition as expected of a de Vries material. Charge control drive produced V-shaped switching with low hysteresis.