Recent progress on silica-based thermooptic switches for ADMs/XCs

Space-division optical switches are key devices for achieving wavelength-division-multiplexing (WDM) optical-path cross-connect (OXC) functions, and optical add/drop multiplexing (OADM) functions for future photonic network systems designed to offer multimedia communication at a high bit rate. Silica-based thermooptic switches, which employ planar lightwave circuit (PLC) technology, are promising devices for use in practical systems. This is because they offer many advantages including low insertion loss, polarization-insensitive operation, long-term stability, the feasibility of large-scale integration, and moreover are suitable for mass-production. In this presentation, we describe recent progress on our silica-based thermooptic switches. The fabricated large-scale thermooptic switches considered include: an N×N matrix switch, a 1×N tree structure switch and an ADM switch