Silica-based optical switch with a single-facet fiber array connection

To reduce the optical fiber interconnection area needed when mounting on a printed circuit board, a silica-based 4×4 thermo-optic matrix switch makes use of a single fiber array connection, with the input and output waveguides of the switch chip located on one side of the chip. The logical arrangement of the switch is based on the path independent insertion loss (PI-LOSS) arrangement whose switch elements are composed of double Mach-Zehnder interferometers. This configuration enables a low insertion loss and high extinction ratio to be achieved. The cost of the module is also reduced as a result of the reduction in the number of fiber connection components.