The position of a target substance existing on the inside of a tissue is grasped in a simpler method. From a first image indicating an intensity distribution of radiation from a subject 5 in a first wavelength region and a second image indicating an intensity distribution of radiation from the subject in a second wavelength region, a surgical microscope system 1 obtains image data of a third image indicating a position of a target substance. Output data obtained by superposing the image data of the third image onto shape image data further includes information indicating the target substance in addition to the image indicating the surface shape of the subject 5. Therefore, the position of the target substance existing on the inside of a tissue can be grasped non-invasively by referring to the output data. Further, the surgical microscope system 1 can grasp the position of the target substance on the inside of the tissue by capturing the first and second images separately from the shape image data and thus makes it possible to grasp the position of the target substance in a method simpler than conventional methods.
