通过很多摄像机坐标系下的点，拟合平面方程，摄像机坐标系下可以得到一条直线方程，光刀平面和靶标平面相交线上每一点的世界坐标(By using the points in many camera coordinate systems to fit the plane equations, a linear equation can be obtained under the camera coordinate system, and the world coordinates of each point on the intersection of the light knife plane and the target plane can be obtained.)