Method of the 3-D curved surface profile measuring and figure processing

Based on the principle of laser triangulation and the technology of modern photoelectric sensor, a laser scanning optical triangulation measuring system which is used to measure 3-D curved surface profile is presented, the system uses a semiconductor laser probe and combines with 2-D grating displacement measuring systems and servo-control systems to realize scanning many points for the measured curved surface. Through the Fourier transform profile detection algorithm with the frequency field low-pass filter performing, computer finishes the real time data processing, the profile of 3-D curved surface is given with high accuracy and high speed. In this paper, the mathematical model of the measuring system is introduced and the jump-error processing method of the objects with large gradient change is discussed in detail. The measuring result shows that the 3-D figure is simple in use, convenient in parameter adjustment, especially, is suitable to measure the objects surface with large gradient and low reflecting ratio.