Three-dimensional shape measuring device

摘要

A three-dimensional shape measuring device comprises a light beam condensing and irradiating system for irradiating a light beam to an object at a fixed angle theta and converging the light beam to a desired minimum diameter at a point A on an optical axis of the light beam, an imaging optical system having an optical axis having an angle phi different from the angle theta and including the point A on the optical axis thereof, for focusing the point A on an effectively constant aperture of a detecting light screen or on a small area, aperture-transmitted light detecting means or photo-electric converter means for detecting light transmitted through the aperture or the small area, detecting position changing means for changing a relative position between the object and the point A, maximum value detecting means for detecting a maximum value of the signal detected by the aperture-transmitted light detecting means or the photo-electric converter means and detection means for detecting a change in the detecting position caused by the detecting position changing means at a time when the maximum value detecting means detects the maximum value. The change in the detecting position is sequentially detected by the detecting means for each of a plurality of points on the surface of the object to measure the three-dimensional shape of the object.