Patent ID: 6859576

Claim:
An optical cross-connect system including M (where M is an even number ≧2) input terminals receiving wavelength-division-multiplexed optical signals and M output terminals receiving wavelength-division-multiplexed optical signals, the optical cross-connect system comprising: a plurality of wavelength division multiplexers/demultiplexers each having two one-side ports and N (where N is an integer >0) other-side ports, performing wavelength division multiplexing/demultiplexing functions; a plurality of optical circulators each connected to one-side port of the wavelength division multiplexers/demultiplexers, respectively, for outputting wavelength-division-multiplexed optical signals received via the input terminals to one-side ports of the wavelength division multiplexers/demultiplexers, for receiving wavelength-division-multiplexed optical signals from one-side ports of the wavelength division multiplexers/demultiplexers, and for outputting the wavelength-division-multiplexed optical signals to the output terminals; a plurality of optical couplers each connected to the N other ports of the wavelength division multiplexers/demultiplexers, respectively, for branching optical signals of individual wavelengths being wavelength-division-demultiplexed, the optical signals being received from the wavelength division multiplexers/demultiplexers; and N optical switching blocks for N wavelengths, for receiving the optical signals branched from the optical couplers according to their wavelengths, switching the optical signals to a desired path, and transmitting the switched optical signals to the desired path, wherein one of the optical signals branched from the optical coupler is input to the optical switching block having a corresponding wavelength and distributed to a desired output terminal, and the other one of the optical signals is input to an optical switching block being out of an operable wavelength range and filtered by the optical switching block.