The end parts of three optical waveguide parts are supported, mutually in parallel, on a substrate, the end part of the center optical waveguide part being one input port and the end parts of other two optical waveguide parts being a first and a second output port,the emitted light from the input port is switched, by means of a first moving mirror and a second moving mirror which are switchingly inserted into positions having the same distance from the end face of the input port, to either the first output port side or the second output port side,the light from the first moving mirror and the light from the second moving mirror being reflected respectively in a first fixed mirror or a second fixed mirror, the light being respectively coupled to the first or the second output port.