Calibration device and method for external field imaging system

The invention relates to a calibration device and method for an external field imaging system. The method comprises the following steps: arranging the external field imaging system calibration device, enabling a structural plate to directly face an imaging instrument, and enabling the lower edge to be horizontal; adjusting the position relation between the structural plate and the imaging instrument, enabling the image center of the imaging instrument to be aligned with the cross center of the cross imaging target, and recording the distance between the structural plate and the imaging instrument; enabling the laser range finder to emit laser for at least two times so as to obtain an actual laser spot on the laser imaging paper; based on the actual laser spot and the laser center point, the deviation between the actual laser spot center position and the theoretical laser spot center position is determined; and calculating the deviation angle between the optical axis of the imaging instrument and the optical a