Integrated liquid-crystal switch for both TE and TM modes: proposal and design

An integrated optical switch is proposed and designed based on a weak-anchoring liquid-crystal (LC) cell with a substrate integrating planar lightwave circuits. It consists of a polarization splitter, two switchable polarization converters and a polarization combiner. The polarization splitter/combiner is a directional coupler with an etched slot and filled-in LC covering layer. The switchable polarization converters are straight waveguides with a designed length and covering LC. The proposed configuration is superior to the existing integrated LC switches, as it works for both the TE and TM modes.