A method for measuring the contours (30) of a three-dimensional object (4); and a method for calibrating an optical system (2, 8). The object (4) is placed into the field of view of the optical system (2, 8). The optical system (2, 8) is activated to obtain a set of data giving a phase (x.sub.t) at each...http://www.google.co.uk/patents/US5557410?utm_source=gb-gplus-sharePatent US5557410 - Method of calibrating a three-dimensional optical measurement system
