The 3D Shape Measurement Of Fourier Transform Profilometery

The research about the traits of all kinds of object's surface is always the issues of many scientists and design teams interested in, in the research process of topography, industry inspection, fluid movement, medical diagnosis, mechanical rotation and lavabo shape, we need to learn about the object's traits by the object's shape, so 3D shape measurement has important meaning and wide application future in these field. Optics'3D shape measurement technology has the character of non-contacting, non-destruction, high accuracy rate, high resolution and quick data obtain rate, so this technology is recognized as the most promising 3D shape measurement method.In optics'3D shape measurement technology, the advantage of Fourier Transform Profilometry(FTP) is that we can restore the object shape just by a picture of a deformation fringe, and has fast collecting data, thus, FTP is well applied in dynamic 3D shape measurement. In the measurement, the basement is to collect measurement information, the most important is to optimize information. This paper mostly makes following job aiming at the measurement information collection and processing:1. Designed the experimental device of optics measurement technology by FTP2. Wrote grating stripe program, project directly onto the object surface through the projector, and collected two-dimensional streaking images by modulation of object shape.3. Wrote relevant program of reappeared 3D shape used Matlab, collected 2d stripes information successfully, and obtained truncation phase.4. Proposed the expanding phase method which is suitable for 3d shape measurement, optimized the expanding phase with method of eight direction gradient interpolation, got the ideal 3D phase distribution.5. Deduce the relationship between phase and height, obtained the under tested 3D shape by unfolding 3D phase distribution, summarized and discussed all of work in detail. This paper makes the reader understand 3D measurement technology of Fourier transform well based on introducing the theory of Fourier transform phase measurement, spectrum filter, the phase extraction and calculation, the phase solution package and analyzing experimental data. This paper completed measuring the object shape used experiment device, which provide a new method for the related research about 3D shape measurement. The theoretical analysis and experimental results show that the 3D measurement technology of FTP is completely feasible under the existing computers and image acquisition technology. As the development of the computer technology and the semiconductor technology, this method will be widely used in topography and geomorphology, machine vision, fluid mechanics, materials deformation, stress analysis, real-time detection, dynamic monitoring .