直线会与前面求得的摄像机坐标系下的相纸靶标平面有一个交点（xc1，yc1，zc1），同理可以得到另外一个相纸靶标平面的交点（xc2， yc2 ，zc2）(The straight line will have an intersection (xc1, yc1, zc1) with the photographic paper target plane obtained in the camera coordinate system a