Liquid crystal optical routing switch

The design and experimental results of a new 2 x 2 optical routing switch based on liquid crystal is reported. The switch uses nematic liquid crystal for polarization beamsplitting and ferroelectric liquid crystal for polarization rotation. The polarization insensitive, broadcast capable, full duplex switch has a signal-to crosstalk ratio of ~20 dB, a switching speed below 250 micros and a measured insertion loss of 1.4 dB. We show that the basic 2 x 2 switch can be extended to form a N x N rearrangeable permutation network.