The radii and the centers of the circles are both unknown.The algorithm uses conics fitting to calculate the images of the circular points from the images of the circles.

• 所用的标定模板由平面上两个相交的圆周组成，且两圆的圆心和半径均未知，通过对两圆的图像进行二次曲线拟合，再根据拟合的二次曲线来计算圆环点图像完成标定过程。