Electrostriction-based orientation control of blue phase I liquid crystal

Abstract

An electric field-based orientation method for blue phase (BP) liquid crystals (LCs) enables particularly high-quality orientation and determines the BPI orientation by applying an out-of-plane electric field in a planar alignment cell. However, the mechanism, including the role of field-induced phases like BPX in BPI lattice reorientation, remains unclear. This study systematically investigates the role of BPX in BPI reorientation under various electric field conditions and alignment layer characteristics. When an out-of-plane electric field was applied, the [110] axis of BPI aligned in the field direction, and the [001] axis aligned along the easy axis. Under an in-plane electric field, the [110] axis aligned parallel to the field, while the out-of-plane orientation depended on alignment treatments. These results reveal that BPI lattice reorientation is determined by the applied field direction and alignment layer characteristics, even when reorientation is mediated solely through BPX. This research offers insights into the BPI orientation dynamics and introduces a method for achieving precise orientation control with reduced field intensities, enhancing the potential for advanced BPLC device applications.