OPTICAL SWITCH, OPTICAL SWITCH APPARATUS AND NODE, AND COMMUNICATION NETWORK

摘要

An optical switch (10) comprising: four optical ports (12, 14, 16, 18); a first optical waveguide (20) coupled between a first of said ports (12) and a second of said ports (14); a first switch element (22) provided between the first waveguide and a second optical waveguide (24) that is coupled to a third of said ports (16); a second switch element (26) provided between the first waveguide and a third optical waveguide (28) that is coupled to a fourth of said ports (18); each said switch element comprising a micro-ring resonator (30, 32) having an active state in which it is coupled to the first waveguide and to a respective one of the second and third waveguides for optical signals at a preselected wavelength, and an inactive state in which no coupling occurs, and each switch element comprising a control element (34, 36) arranged to receive a respective control signal configured to cause it to switch the micro-ring resonator between said states.