Electro-optical property in hybrid aligned reverse mode cell using liquid crystals with positive and negative dielectric constant anisotropies

Abstract

We have proposed polymer stabilized liquid crystal (LC) cells with a hybrid alignment nematic (HAN) LC. LCs with positive and negative dielectric constant anisotropies are used. The cell has a reverse mode electro-optical property which shows a transparent state in a voltage off-state and a light scattering state in the on-state. We fabricate cells by irradiating the cell with a UV light from a planar alignment side or vertical alignment side in a polymerization process. The photopolymerization-induced segregation of the polymer from the LC and the influence of UV absorption by the LC bulk are investigated. A relationship between UV irradiation conditions and electro-optical characteristics in the cell is clarified. The light scattering intensity depends on an incident angle of light in the on-state, which is promising for application to smart windows. The feasibility of this concept is demonstrated with consideration of LC materials.