Patent ID: 7272317

Claim:
An optical multiplexed signal demultiplexing device for demultiplexing optical multiplexed signals in which a plurality of optical signals having an identical carrier frequency are multiplexed, into the plural of optical signals, comprising: an optical amplitude control unit configured to control light intensities of input optical signals to obtain the optical multiplexed signals having different amplitudes for different communication channels from the input optical signals in which a plurality of optical pulse sequences having an identical amplitude for all communication channels are multiplexed on a time axis; an optical frequency conversion unit having an optical nonlinear medium that changes a refractive index according to light intensities of input lights, and configured to carry out a frequency conversion of the optical multiplexed signals having different amplitudes for different communication channels into a plurality of optical pulse sequences having different carrier frequencies for different communication channels; and an optical frequency selection unit configured to demultiplex the plurality of optical pulse sequences obtained by the frequency conversion into optical pulse sequences for different communication channels, by selectively separating optical signals according to frequencies.