Calibrating method and calibration apparatus

A calibration apparatus comprising:

• circuitry configured to:
• control a laser radiator to radiate calibration laser light to an object such that a pattern is projected in a laser coordinate system with respect to the laser radiator;
• control a camera to obtain a first image of first light points of the calibration laser light projected on a surface of the object when the object is in a first position;
• calculate, based on the first image, three-dimensional positions of the first light points in a camera coordinate system with respect to the camera;
• change a position of the object from the first position to a second position;
• control the camera to obtain a second image of second light points of the calibration laser light projected on the surface of the object when the object is in the second position;
• calculate, based on the second image, three-dimensional positions of the second light points in the camera coordinate system;
• and
• calculate a positional relationship between the laser coordinate system and the camera coordinate system based on the three-dimensional positions of the first light points and the three-dimensional positions of the second light points.