Polarization-independent liquid crystal lens with four liquid crystal layers

A polarization-independent liquid crystal (LC) lens is reported. There are four LC layers in the LC cell. Two LC layers focus one polarization component of an incident light wave, and the other two LC layers focus the other polarization components. The former two layers are placed interlacedly with the later two layers, so that the inherent position difference between the foci of the two polarization components may become very short. The lens properties are shown experimentally.