The present invention concerns a Michelson-type interferometer (1) for measuring the intraocular axial length (AL) comprising: an arrangement (7) able to move apart and come near with respect to an emitting light source (5), said arrangement (7) comprising at least a first (8) and second (9) at least partially reflecting surface arranged at a pre-determined mutual distance (d) a motorized driving system (500) to command the movement of the reflecting arrangement (7) wherein said motorized driving system (500) is controlled in such a way that the scanning is completed in a single translation stroke in a direction starting from an initial position in which the first surface (8) generates the first interference peak at the beginning of the translation and with such a fixed distance (d) between the plates that afterwards during said translation the second plate (9) generates the second interference peak.
