Dispersion measurement device and dispersion measurement method

A dispersion measuring device comprising:

• a light source configured to output initial pulsed light;
• a control unit configured to store a first phase pattern and a second phase pattern and selectively output the first phase pattern and the second phase pattern, the first phase pattern and the second phase pattern being phase patterns presented in a spatial light modulator in order to generate modulated light by applying a predetermined phase shift for each wavelength to the initial pulsed light;
• a pulse forming unit including the spatial light modulator configured to present a phase pattern output by the control unit, the pulse forming unit forming, from the initial pulsed light, an optical pulse train that is the modulated light including a first optical pulse of which a center wavelength is a first wavelength and a second optical pulse of which a center wavelength is a second wavelength shorter than the first wavelength;
• a light detection unit configured to detect a temporal waveform of the optical pulse train;
• and
• an arithmetic operation unit electrically connected to the light detection unit, wherein
• a measurement object is disposed on an optical path between the light source and the pulse forming unit or an optical path between the pulse forming unit and the light detection unit,
• the arithmetic operation unit estimates a wavelength dispersion amount of the measurement object based on a feature amount of the temporal waveform,
• the first optical pulse and the second optical pulse have a time difference from each other,
• the first phase pattern is a phase pattern for applying the predetermined phase shift for each wavelength to the initial pulsed light so that the first optical pulse is generated after the second optical pulse, and
• the second phase pattern is a phase pattern for applying the predetermined phase shift for each wavelength to the initial pulsed light so that the second optical pulse is generated after the first optical pulse.