Abstract: An apparatus for dimensional inspection of an object. The apparatus is adapted to produce a slender beam of measuring radiation for irradiating an object under examination. Reflected light image receiving means are provided including a receiving lens for collecting radiation reflected from an object surface spot irradiated by the measuring beam, and a linear photo-sensitive detector. The receiving lens is dimensioned and disposed relative to the measuring beam and the linear detector as to exclusively project those object surface spots irradiated by a longitudinal section defining a measuring range, of the measuring beam, as focussed dots on the linear photo-sensitive detector area. For improving the resolution of the focussed dots produced on the detector, a beam forming lens is provided for causing the cross-sectional area of the measuring beam to gradually increase over the measuring range.