Determination of polar anchoring strength for polymer-stabilized blue phase liquid crystal device

Quantitative evaluation of a coupling coefficient between the blue phase (BP) liquid crystal (LC) and the diacrylate-type polymer, which is to be either the framework or the defect line of the polymer-stabilized (PS) BPLC, is an important subject. As a coupling coefficient, the polar anchoring strength W_d between the BPLC and the diacrylate-type polymer prepared inside a thin hybrid alignment nematic (HAN) cell was evaluated by means of oblique incidence transmission spectroscopic ellipsometry. As an example, the polar anchoring strength W_d = 1.87 × 10^-4J/m² is measured at the interface between host BPLC material with the diacrylate-type polymer performing vertical alignment (VA).