Simple and Flexible Calibration Method of a 3D Imaging System Based on Fringe Projection Technique
Phase calculation-based 3D imaging systems have been widely studied in academia and applied in industrial fields.A vital step of such 3D systems is calibration,which builds up the relationship between an absolute phase map and shape data.The existing calibration methods are complicated because of using a precise translating stage or a 3D gauge block.This paper presents a simple and flexible calibration method of phase calculation-based 3D imaging systems by using a checkerboard with known checker size and a white plate having discrete markers on the surface with known distance in between.Placing the checkerboard at several positions determines the internal parameters of the CCD camera of 3D imaging systems.The plate gives phase and depth data in the measuring volume to build up their relationship by a polynomial function at each pixel position.At each plate position,the absolute phase of each pixel can be calculated by projecting three fringe pattern sets with the optimum fringe numbers onto the plate surface.In the meanwhile,each marker position of the plate can be determined by an automatic extraction algorithm,so the relative depth of each pixel to a chosen reference plane can be obtained.Therefore,coefficient set of the polynomial function at each pixel are calculated by using the obtained multiple absolute phase and depth data.The X,Y coordinates and the pixel positions can be established by the parameters of the CCD camera and the calibrated depth data.Experimental results and performance evaluations show that the proposed calibration method can easily build up the relationship between absolute phase map and shape data in a simple and flexible way.
3D calibration fringe projection 3D imaging absolute phase calculation.
Zong-Hua Zhang Sha-Sha Meng Shu-Jun Huang
School of Mechanical Engineering, Hebei University of Technology, Tianjin, China
国际会议
天津
英文
101-105
2012-10-16（万方平台首次上网日期，不代表论文的发表时间）