针对长距离时外参数标定实际操作难度较大，本文将标定靶杆作为外参数标定的媒介，而后采用双目交会方法进行相关精度验证。通过分析标定靶杆上合作标志物的世界基准坐标系坐标误差对相机内外参数的影响，从而确定最终双目交会时对实测合作目标的世界基准坐标系的影响。实验结果表明，为了使得合作标志物的测量坐标在项目要求的10 mm 精度范围之内，标定杆上合作目标的大地测量X 轴坐标精度须在0.621 9 mm 以内，Y 轴上坐标精度为13.341 2 mm，Z 轴坐标误差为0.729 1 mm。

In order to overcome the difficulty during measuring the external parameters of the camera with a long object distance, a calibration target bar was used as a medium. Its precision can be verified by the binocular vision measurement. By means of analyses of the influence of the cooperative targets’ coordinate in the world coordinate system on the internal and external parameters of the camera, the influence of the measured cooperative targets’ coordinate by the binocular vision measurement can be determined. The result shows that the geodetic coordinate error of the cooperative targets in the calibration target bar can affect the measurement error of the measured cooperative targets. The result shows that, for the propose that the measurement precision requirements of the cooperative targets should reach 10 mm, the X axis precision requirement should be 0.621 9 mm, the Y axis is 13.341 2 mm, and the Z axis is 0.729 1 mm.