Helical-Axis Alignment Formation by Concentration Gradients of Chiral Liquid Crystal Polymers Induced by Photogradient Polymerization

Abstract

Chiral nematic liquid crystals, which forms helically twisted molecular alignment, exhibit the distribution of refractive index along the helical axis. Controlling the helical-axis alignment enables us to express their optical properties. For instance, controlling in-plain alignment of helical axis generates a selective reflection property, whereas controlling out-plain helical-axis alignment generates a diffraction and polarization conversion properties. However, the arbitrary controlling method for the helical-axis alignment has not yet been established. Previously, we found that the helical-axis alignment was aligned in photopolymerization process with an intensity-gradient patterned light. In this study, we discussed the formation mechanism of the helical-axis alignment.