Summary: | 碩士 === 國立臺灣大學 === 機械工程學研究所 === 96 === This thesis studies an intensity correction method to reduce errors induced by color coupling and color imbalance for measuring 3D shapes of objects. First, 3D look-up table (LUT) is established for storing the difference between the assigned projected intensities and the measured intensities. Our objective is to find he corresponding input color given the measured color, which is the reverse process of the creation of the look-up table. For this purpose, we developed a search algorithm. The two methods are developed to compensate for errors caused by color coupling and imbalance. In addition, the two methods are used to further reduce nonlinear digital fringe error. An integrated program is developed by combing phase-shifting process, phase-wrapping process, phase-unwrapping process, and intensity correction. With the developed program, several measurement examples are investigated. The results demonstrate that the purposed advanced error correction strategy offers good feasibility for improving the quality of reconstructed 3D shapes.
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