Design and performance of a reconfigurable liquid-crystal-based optical add/drop multiplexer

The authors describe a reconfigurable optical add-drop multiplexer designed for 50-GHz channel spacing over either the C- or L-bands. The system may also function as a variable optical attenuator. The design features a reflective liquid-crystal modulator, a compact free-space spectrometer, polarization diversity, and fine-scale attenuation control.