Abstract: The developed device for studying an object ensures straightforward ultimate matching between the arms of an optical interferometer and therefore, high in-depth resolution when being used in clinical and industrial applications. According to the invention at least one arm of the optical interferometer of the device comprises at least one replaceable part with preset optical properties. The preset optical properties of the replaceable part of the one arm of the optical interferometer are determined by the optical properties of at least a part of the other arm of the optical interferometer, such as of the optical fiber probe. That makes it possible, for example, to supply the device with a kit of replaceable sets, which include an optical fiber probe and a replaceable part of the reference arm made of the same reel of optical fiber. Using these sets in clinical and industrial applications is most effective and does not call for highly qualified personnel.