目的:根据空间距离不变性，与它周围的点的距离不变，先列出一个点与周围点的 距离，计算同一点分别在两个视场的三维坐标与周围距离差，并计算出其误差-Objective: according to the space distance invariability, and point the distance around it is changeless, first list around a point and point