Solid-state optical switches using planar lightwave circuit and IC-on-PLC technologies

Abstract

We review recent progress on optical switches that employ silica-based planar lightwave circuits (PLC) including a 16 x 16 matrix switch, a 1 x 128 switch, an 8-channel 1 x 8 switch array, and a 32-channel 2 x 2 switch array. These switches are composed of silica-based waveguides and have a solid-state structure with no moving parts, thus they exhibit low insertion loss, high repeatability, and excellent long-term reliability. We also describe IC-on-PLC technology, where IC chips are integrated on the PLC surface for higher functionality and greater compactness. We report the results of reliability tests on the PLC switches, and show that they can put to practical use.

Scalability of Multi-Stage Nested Mach-Zehnder Interferometer Optical Switch with Phase Generating Couplers

“…In optical fiber communication systems, optical switches are employed to route the optical signals passing through a node without any conversion into electrical signals. Among various types of optical switches, those based on silica waveguides have many advantages [1][2][3][4][5]. Wafer-level fabrication process enables large-scale integration and mass productivity.…”

“…Physical and chemical stability of silica as well as the absence of moving mechanical parts offer high reliability. The silica-based optical switches with thermo-optic phase shifters have been investigated since as early as 1980s [1], and their excellent performance as well as high feasibility has been well qualified [2]. They have been deployed in reconfigurable optical add/drop multiplexing (ROADM) systems in 2000s [3], where their millisecond response time is sufficient for this application.…”

Nested Mach–Zehnder interferometer optical switch with phase generating couplers

“…Optical switches which can route optical signals without optical/electrical conversion are indispensable for reconfigurable optical networks. [1][2][3][4][5] Silica-waveguide optical switch based on thermo-optic effect [6][7][8] has been widely deployed because it has advantages including compact integration, mass producibility, and good reliability. Recently, its application to data center network is considered, [9][10][11] where switching speed is an issue.…”

Design of arrayed-waveguide optical switch employing window function for crosstalk reduction

“…Among various kind of optical switches, 3,4) a waveguidetype switch is most promising because it has many advantages including compact integration, mass producibility, and good reliability. 5) The waveguide-type optical switch is composed of multiple switch elements. The switch element commonly used is a Mach-Zehnder interferometer (MZI) with a phase shifter.…”