Patent ID: 8605357

Claim:
A wavelength selective switch, comprising: a polarization controller configured to control a polarization plane of a first optical signal as wavelength-multiplexed light input through a first input port, and to control a polarization plane of a second optical signal as wavelength-multiplexed light input through a second input port such that the polarization plane of the second optical signal is aligned in a direction different from the polarization plane of the first optical signal; a wavelength demultiplexer configured to wavelength-demultiplex optical signals wavelength multiplexed in the first optical signal and the second optical signal, the direction of the polarization plane of which is controlled by the polarization controller; a polarization separator configured to separate, according to the direction of the polarization plane, the optical signals wavelength-demultiplexed by the wavelength demultiplexer; an optical collector configured to collect the optical signals separated by the polarization separator; an optical signal reflector configured to reflect the optical signals collected by the optical collector; and a reflection controller configured to control the optical signal reflector in accordance with an incident position of the optical signal incident on the optical signal reflector such that the optical signal wavelength-multiplexed in the first optical signal is output from a first output port corresponding to the first input port and such that the optical signal wavelength-multiplexed in the second optical signal is output from a second output port corresponding to the second input port.