Patent ID: 11913836
Assignee: HAMAMATSU PHOTONICS K.K.
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G

Claim 0:
1. A dispersion measurement apparatus comprising:
a pulse forming unit including a spatial light modulator, and configured to form a light pulse train including a plurality of second light pulses having time differences and center wavelengths different from each other from a first light pulse output from a light source, the spatial light modulator being used to form the light pulse train;
a beam splitter configured to branch the light pulse train output from the pulse forming unit and passed through a measurement object into a first light pulse train and a second light pulse train;
an imaging unit including an image sensor, and configured to disperse and image the first light pulse train branched by the beam splitter, and generate imaging data by the image sensor for each second light pulse included in the first light pulse train;
a spatial filter unit configured to receive the second light pulse train branched by the beam splitter, and extract light of one or a plurality of partial regions in a cross section intersecting with a traveling direction of the second light pulse train;
a correlation optical system including an optical element, and configured to output correlation light including a cross-correlation or an autocorrelation of the light of the one or plurality of partial regions extracted by the spatial filter unit, the optical element being configured to generate the correlation light;
a photodetector configured to detect a temporal waveform of the correlation light output from the correlation optical system; and
a processor configured to estimate a wavelength dispersion amount in the measurement object based on a feature value of the temporal waveform, wherein
in the spatial filter unit, a spatial position of the partial region in the cross section is changeable.