Light induced gradient polymer stabilized liquid crystals for electrically variable focus lenses: the role of network morphology

We describe the electro-optical behavior of polymer stabilized liquid crystal (PSLCs) networks used for the development of electrically variable focus lenses. We start with a short review of mechanisms influencing the performance of those lenses, including the most important one : the light scattering. Then the role of the polymer chain morphology in electrically controllable molecular reorientation and formation of orientation defects in PSLCs is investigated. We use two non mesogene monomers, with respectively one and two functionalities, to create two different degrees of cross-linking in PSLCs. By using optical polarimetry and scattering experiments, we investigate the defect formation in those PSLCs, outline the presence of 3D orientational defects and show that the PSLCs with higher crosslinking demonstrate better electro-optical reversibility.