Abstract: A device for measuring heights and/or thicknesses on a measurement object, includes (i) a first low-coherence interferometer for combining, in one spectrometer, a reference optical beam and a measurement optical beam originating from reflections of the light on interfaces of the measurement object, to produce a grooved spectrum signal with spectral modulation frequencies, (ii) apparatus for measuring an item of position information representative of the relative optical length, (iii) electronic and calculating apparatus arranged for determining at least one spectral modulation frequency representative of an optical path difference between the measurement optical beam and the reference optical beam, and for determining, by exploiting the item of information and the spectral modulation frequency, at least one height and/or thickness on the measurement object, and (iv) second optical apparatus for measuring distance and/or thickness with a second measurement beam incident on the measurement object on a second fa