| Structured light 3D measuring technology uses computer vision theory to measure and reconstruct the objects to get their 3D model. It is a non-contact measuring method developed based on the method of laser spot scanning in recent years with widely practicability.Time encoded methods encode by projecting black-white stripe pattern to the object mostly, but the disadvantage is the white stripes diffuse towards the black stripes in the images taken by camera. In order to solve the problem, a color encoded method for structured light system is presented in this thesis based on the research of structured light technology for 3D measurement. The method uses the projector to project a set of color encoded pattern to the object in time sequence. The color encoded pattern is composed of red, green and blue stripes. Then the camera takes the images from a certain angle. The projecting angle of every point in the center of the green stripes in the images can be determined. Then the 3D data of the point on the measured object surface can be calculated by the system mathematical model.The main research in this thesis is as following: firstly, the RGB color Gray encoded pattern is designed and the decoded scheme for the images is presented. Secondly, 3dmax software is used to simulate the projector, the camera, the measured object and the 3D measuring process. Finally, Matlab is used to compile the program for processing the image and calculating. A conversion method from RGB color image to HIS color image is adopted. In addition, the stripe center precision location method based on the HIS color image segmentation and the sub-pixel location technology is adopted. Then the encoded pattern decoding, the calculation of 3D coordinates and the reconstruction of the surface of the 3D objects are completed.This thesis measured and reconstructed the analytic object and non-analytic object as plane, sphere and cone by simulation experiment and analyzed the experimental results.
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