Optical waveform shaping method and optical waveform shaping apparatus

An optical waveform shaping apparatus for collectively waveform shaping a plurality of signal lights of different wavelengths contained in a WDM signal light, comprising:

• a spectrum expanding section configured to have a first nonlinear medium to which the WDM signal light is input, and to collectively expand a spectrum of the signal light of each wavelength contained in the WDM signal light in the first nonlinear medium, and to separate a signal component and a noise component which are contained in each signal light, into different spectrum regions;
• a first optical filter adapted to collectively extract a signal component in a spectrum region on a shorter wavelength side of a center wavelength of each signal light for when each signal light contained in the WDM signal light has been input to the first nonlinear medium, for each signal light of which spectrum has been expanded by the spectrum expanding section, and to collectively remove the signal component and the noise component in the other spectrum region;
• and
• a wavelength shifting section configured to have a second nonlinear medium to which is input the signal component of each signal light, which has been extracted by the first optical filter, and to collectively shift a wavelength of the signal component of each signal light by self-frequency shifting generated in the second nonlinear medium, and to substantially match a center wavelength of each signal component with the center wavelength of each signal light for when each signal light contained in the WDM signal light has been input to the first nonlinear medium.

An optical waveform shaping method comprising:

• an expanding process of inputting a plurality of signal lights of different wavelengths to a first nonlinear medium to expand spectrums of the signal lights;
• a filtering process of extracting a signal component which does not contain a noise component from a spectrum region on a shorter wavelength side of a center wavelength of each signal light of which spectrum has been expanded in the expanding process;
• and
• a process of shifting a wavelength of the signal component of each signal light extracted in the filtering process to a longer wavelength side due to self-frequency shifting generated in a second nonlinear medium, and substantially matching a center wavelength of the signal component of each signal light with the center wavelength of each signal light for when each signal light has been input to the first nonlinear medium.