A novel 2D pattern used in camera calibration is presented. An array of circles with one feature circle located at the center is photo echoed on the pattern. According to the category of the pattern, an ellipse recognition algorithm is proposed. It facilitates acquisition of the distinguished points without human operation. The 3D space coordinate system of these points can be established automatically and accurately. A series of experiments show that the algorithm is robust and reliable. The calibration error is less than 0.4 pixels. The new ellipse recognition algorithm can be widely used for computer vision applications.