| 360° shape measurement of the objects is widely used in the area of CAD/CAM, reverse engineering, rapid prototyping and multimedia. Fourier transform profilometry (FTP) only needs one fringe pattern to accomplish 3-D measurement. Meanwhile, it can acquire and process object's data in high speed and high precision. On the basis of reviewing the 3-D measurement methods, application prospect of 3-D measurement, we discuss all the details of FTP, including theoretical analysis, filtering in frequency domain, calculating and unwrapping the 3D phase. With the following merits of linear CCD: small size, high resolution and real-time transmission of signals, we propose a method to accomplish '360?shape measurement of the rotary objects. In this method, we place the objects on the rotary work stage, project laser sheet to sine grating to generate structured illumination field, use linear CCD to capture the deformed fringe, and use FTP to process the data of the objects. In this thesis, we analyze the basic property of Fresnel diffraction with fan-shaped laser sheet illumination, and discuss the distinctive merits of such 1 -D distributed structured illumination fields, such as wide view and measuring range, simple setup, easy to be adjusted, etc., We have designed theexperimental measurement system, driver circuit of linear CCD, data collecting and processing circuit, and the controls circuit of the rotary work stage. Using single-chip unit as central processing unit, we transfer the data of the deformed fringe to higher computer with serial port. We form the 360 3-D scanned data by data matching. Using FTP, we reconstruct the 360 shape of the objects. In this paper, we also discuss the problems of system error and system calibration.Compared with the traditional methods, this method can improve the resolution. The experiments show that this method can correctly reconstruct the shape of the objects. We believe it has a great application value in the area of 3-D shape measurement.
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