A novel color coding method for structured light 3D measurement

作者：Huang Junhui^*; Wang Zhao; Gao Zhihua; Gao Jianmin

来源：Conference on Videometrics, Range Imaging, and Applications XI, 2011-05-25 to 2011-05-26.

DOI：10.1117/12.889317

• 3D measurement
• structured light
• digital fringe projection
• color coding
• color crosstalk
• system calibration

This paper presents a novel color coding method which is applied to structured light measurement using fringe-pattern projections. The method is based on time coding, and reduces the projection times of fringe patterns with the same number of fringes by adding colors into the conventional fringe patterns. But the introduction of colored fringes also brings a difficulty in image processing, that is color crosstalk. To address this problem, sinusoidal fringe patterns with four colors of white, red, green and blue are used to project to the measured object surface to reduce the edge effect. Based on those ideas and methods, a three-dimensional measurement system is built, and the direct linear transform (DLT) method of calibration with lens distortion corrected by cross ratio invariance principle is used to calibrate the internal and external parameters of the system. Then the parameters of the system are optimized by the bundle adjustment method. Finally, a standard metal hemisphere with spraying is measured, and the experimental results show that with the same times of projection, the lateral measurement resolution is higher than the traditional method, and the measurement accuracy of the depth direction is about 0.27mm.

• 出版日期2011
• 单位西安交通大学; 机械制造系统工程国家重点实验室