A measurement optical system (30) is provided which causes measurement light split by a beam splitter (20) to be incident to an object, and a reference optical system (40) is provided which causes reference light split by the beam splitter to be incident to a reference mirror (49). A tomographic image of the object is formed on the basis of interference light generated by superposition of the measurement light reflected at the object to return and the reference light reflected at the reference object to return. Optical components such as lenses and mirrors that constitute the measurement optical system and reference optical system correspond to each other, and the wavelength dispersion characteristics of the optical components in the correspondence relationship are identical or equivalent.
