Abstract: A microscope (1) arranged for measuring microscopic structures uses punctiform bundles of rays from a point source (31, 34) of light focused by an optical system on a structure to be measured so that a photoelectric detector (15) can receive the ray bundles reflected from the structure. Plane plates (30a,30b) arranged in a non-parallel ray portion of the path of the optical system can be pivoted through predetermined angles for moving the focal point of the ray bundles on the structure. Encoders (61a, 61b) are coupled with the plates and arranged for measuring the pivot angles used in moving the focal point; and a processor (20) supplied with signals from the encoders and from the detector (15) is arranged for calculating the linear dimensions of the structure over which the focal point has moved.