Realization Of Profilometry System Based On Digital Projection

As the development of modern technique of measurement,the traditional measurement is out of date.With the advantage of non-contact,automatic,adaptable,3D Shape Measurement has been widely concerned and used.In this paper, Three-dimensional Fringe pattern Profilometry is the most popular measurement of the tchniques,the study of wich has profund value of research and practical meaning.The basic principle of Three-dimensional Fringe pattern Profilometry is to project a grating fringe pattern on the surface of the measured object,and then a distorted pattern caused by the hight of the object is recorded by a camera,the sharp of the object is rebuilt rebuild by the processing of the the computer. In this paper,Fourier Transform Profilometry and Phase Measuring Profilometry are studied,and the comparison of the two measuring methods is given.Based on the principle, an experimental system is set up by the author,which is mainly composed by a CCD camera ,a projector and a computer.The hardware devices were selected,and based on MATLAB platform of windows,the control software were edited.To take a spherical crown for example, Fourier Transform Profilometry and Phase Measuring Profilometry were usd to measure the sharp by the experimental system,and the results demonstrated that Phase Measuring Profilometry is superior to Phase Measuring Profilometry.At the end of this paper,the error of the system and algorithm is analyzed,in addition,the effrct of the non-linear character and filter to the system have been studied.As to the key point of Phase Unwrapping,a method of unwapping is given to increase the accuracy of the system.