Liquid-crystal polarization rotator and a tunable polarizer.

A liquid-crystal (LC) voltage-controlled linear polarizer is demonstrated using two LC retarders stacked with two quarter-wave plates and an intermediate linear absorptive polarizer. The device was examined experimentally using unpolarized light and was found to be in accordance with the theoretical prediction. Under certain conditions the device acts as a polarization rotator with possibility for simultaneous amplitude modulation. Hence it has a potential application in high-dynamic-range polarimetric imaging.