Patent ID: 7440648

Claim:
An optical switch comprising: an optical input/output section, in which at least one input port and a plurality of output ports are arranged in a first direction; a spectroscopic section, that separates a wavelength multiplexed light containing a plurality of wavelength channels, outgoing from said input port, in a second direction different from said first direction according to their wavelengths; a plurality of movable mirrors that reflects each wavelength channel separated by said spectroscopic section by respective reflecting surfaces whose angles are variable; and a movable mirror driving section that sets the angles of the reflecting surfaces of each of said movable mirrors such that each of the wavelength channels reflected by each of said movable mirrors is inserted via said spectroscopic section into an output port set in an output address of an appropriate wavelength channel among said plurality of output ports, wherein there is provided: a reflection section, that is provided on the end face of each of said output ports, and reflects part of the wavelength channel injected from each of said movable mirrors via said spectroscopic section; a reflected light extracting section for obtaining light reflected by said reflection section and returned to said input port, from said input port; and a reflected light monitor section for monitoring the power of the reflected light obtained by said reflected light extracting section corresponding to each of the wavelength channels.