Optical beam-shifter module with high extinction ratio for 1024-input-port optical-switching network

An optical beam shifter module consisting of liquid-crystal cells and a birefringent plate is investigated for a 1024-input-port switching network. High extinction ratio (> 20 dB) and low insertion loss (0.5 dB) are achieved by optimal device design. Precise optical alignment is obtained without any adjustment mechanism by using assembly baseplate and an optical assembly bench.