Quantitative comparison or calculation of a plurality of images in different transmission bands is facilitated even if the transmission bandwidth of the spectroscopic element is different at different wavelengths. Provided is a spectroscopic device (1) including: a tunable spectroscopic element that changes the transmission band of light passing through coating layers provided on a plurality of optical substrates facing each other with a distance therebetween by adjusting the optical path length between the coating layers; an image acquisition section for acquiring an image of the light transmitted through the tunable spectroscopic element to acquire a spectroscopic image; a storage section (18) for storing information about spectral characteristics corresponding to the wavelength of light transmitted through the tunable spectroscopic element; and an image correction section (21) for correcting the spectroscopic image acquired by the image acquisition section using the information about the spectral characteristics stored in the storage section (18) with respect to each wavelength of light transmitted through the tunable spectroscopic element.