Coherence scanning interferometer for spatially resolved optical measurement of the height geometry data of an object, comprising an optical path-length-changing unit, a measuring light source , an interferometer and a measuring detector having a detection surface, which detection surface has a multiplicity of photosensors at different locations, wherein the interferometer is configured to co-operate with the measuring light source and the measuring detector in such a way that an output beam generated by the measuring light source is split into a measuring beam and a reference beam by means of a beam splitter of the coherence scanning interferometer, the measuring beam is imaged two-dimensionally into an image plane of the measuring detector, which image plane forms the measuring plane of the coherence scanning interferometer, so that in the measuring position, when an object is arranged in the measuring plane, the measuring beam is incident two-dimensionally on the object and the measuring beam at least partly reflected and/or scattered by the object is coupled into the beam path of the interferometer again and imaged onto the detection surface of the measuring detector and superposed with the reference beam in such a way that the superposed measuring beam and reference beam two-dimensionally overlap the multiplicity of photosensors, wherein the optical path-length-changing unit is configured to change the distance between the object and the measuring plane, and wherein the coherence interferometer is configured to image the object arranged in the measuring plane onto the detection surface with an imaging depth of field, characterised in that the coherence scanning interferometer additionally comprises a focussing light source , which focussing light source is configured to co-operate with the coherence scanning interferometer in such a way that a focussing beam emitted by the focussing light source is imaged with a focussing depth of field via the beam splitter into an image plane of the focussing light source, which image plane of the focussing light source is identical with the image plane of the measuring detector and forms the measuring plane of the coherence interferometer; and the focussing beam at least partly reflected and/or scattered by the object is imaged onto a focus detector , wherein the focussing depth of field is smaller than the imaging depth of field, and the interferometer comprises an optical main lens which is arranged in the beam path of the interferometer in such a way that at least the measuring beam at least partly reflected and/or scattered by the object arranged in the image plane of the measuring detector is imaged at least via the main lens onto the photosensors of the measuring detector; and the focussing light source is arranged in the beam path of the coherence scanning interferometer in such a way that the focussing beam is imaged onto the object via at least one optical focussing lens in such a way that the imaging of the object onto the measuring detector is effected with a numerical aperture A N,O and the imaging of the focussing light source onto the object is effected with a numerical aperture A N,F , the aperture A N,O being smaller than the aperture A N,F . <EOS>