Spectrometer

A spectrometer comprising:

• a spectroscopic element configured to change a wavelength of light to be transmitted and to spectrally disperse light from a target;
• an element control section configured to control operation of the spectroscopic element;
• an imager configured to receive the light transmitted through the spectroscopic element and to acquire at least one spectral image for each of a plurality of the wavelengths obtained by spectral dispersion, the imager acquiring a plurality of spectral images corresponding to the plurality of wavelengths for a target that moves relative to the imager at acquisition timings different from each other;
• a shift amount acquisition section configured to, using information on the relative movement, acquire a relative positional shift amount between a first spectral image that is one of the plurality of spectral images and a second spectral image that is another one of the plurality of spectral images;
• and
• a position alignment section configured to perform, using the positional shift amount acquired by the shift amount acquisition section, position alignment between the first spectral image and the second spectral image by correcting a position of the second spectral image with respect to a position of the first spectral image.