The present invention provides a method for designing an optical pulse
shaper including a first optical propagation line unit having a nonlinear
medium and a dispersion medium concatenated, including: specifying design
specifications of the first optical propagation line unit; and based on
the design specification, calculating a quasi-periodic stationary pulse
of which a waveform of an input optical pulse to the first optical
propagation line unit is similar to a waveform of an output pulse from
the first optical propagation line unit.