Analysis of phase retardation profiles in liquid crystal microlenses with different nematic alignment

We study the phase retardation profiles in LC-microlenses with homeotropic, planar and hybrid alignment. W□ show that the reorientation process of a homeotropically aligned nematic in a LC-microlens takes five stages characterised by different phase profiles. In the case of a planar or hybrid microlens, there are four stages. The voltages at which the configurations change from one to another are determined by the diameter of the microlens and its alignment type. The phase profile analysis reveals defocusing properties of homeotropically aligned LC-microlenses, while the planar and hybrid microlenses are focusing at low voltage and defocusing at high voltage