Low loss fully reconfigurable wavelength-selective optical 1×N switch based on transversal filter configuration using silica-based planar lightwave circuit

A low loss wavelength-selective switch is proposed and demonstrated. The switch has a 1×4 transversal filter configuration that includes arrayed waveguide gratings and thermooptic phase shifters, and can route arbitrary wavelength input light to arbitrary outputs with no loss variation. We confirmed its operating principle and obtained an average loss of 2.7 dB and a worst extinction ratio of more than 20 dB.