3-D Shape Measurement Based on Optic Interferometric Projection

This paper aimed to use a novel optic interferometric fringe projection to measure the three-dimensional shape of small object with high resolution. In this method, the projecting fringe pattern, which has a sinusoidal density distribution, good contrast and equal spacing, is generated by a spherical wave incident into a triangle-section prism. Project the fringe onto the subject under test, the image of the deformed fringe pattern modulated by object surface is captured by a highspeed CMOS camera and processed by the Fourier Transform technique to extract the phase distribution which is related to height information. An experimental system is set to conduct 3-D shape measurement and the result shows the validity of the proposed method. The projecting system is simple and compact, which helps to realize the integration and miniaturization of the system.