系统参数的标定是结构光三维测量系统工作的基础, 且参数标定的精度直接影响测量的精度, 其中投影仪目前还存在标定过程复杂、精度较低等问题。为解决该问题, 通过投影一组圆阵图案到一块本身带有特征圆的平板上, 并由摄像机拍摄; 基于二维射影变换理论, 通过误差补偿法建立投影仪图像坐标和摄像机图像坐标的对应关系, 利用该对应关系计算获取标定点的投影仪图像坐标; 以标定点的两组图像坐标和世界坐标为初始值, 使用非线性算法对系统进行全参数整体优化, 完成系统的标定。实验验证了系统标定误差最大值小于0.05 mm, 误差均方根小于0.03 mm, 结果表明该方法标定过程简单, 能够有效地提高标定精度, 具有较广的适用性。

Calibration of the system parameters is the basis of three-dimensional measurement system of the structured light, and accuracy of parameter calibration directly affects accuracy of the measurement, in which the projector still has the problems of complex calibration process and low precision. In order to solve this problem, a calibration method is put forward, which is done by projecting circles pattern to a flat with circular signalized points. Based on projective transformation theory, projective corresponding relation is established between projector image coordinates and camera image coordinates through error compensation method, and accurate projector image coordinates of calibration points is obtained. Taking two groups of image coordinates and world coordinates as initial value, nonlinear algorithm is used to optimize the whole system parameters. Experimental results show that the maximum error of the system is less than 0.05 mm and the error root mean square is less than 0.03 mm. The results show that the calibration process is simple and can improve the calibration accuracy and has wide applicability.