Three-camera three-dimensional endoscope

The invention discloses a three-camera three-dimensional endoscope, which can be calibrated in a normal using process without the assistance of an external calibration module. Specifically, the three-dimensional endoscope is used by the following steps: firstly, conducting initial calibration on three endoscope cameras by virtue of a calibration plate, so as to acquire corresponding initial calibration parameters; and secondly, under the circumstance of guaranteeing parameters of two cameras unchanged, conducting zooming in/out or focusing adjustment on the other camera, acquiring three images which are shot by the three adjusted cameras at a same moment, conducting characteristic point detection and matching operation on an overlap area of the three images, on the basis of a characteristic point matching result of the three images, calculating three-dimensional coordinates of characteristic points in a designated coordinate system through 3D reconstruction, calibrating a to-be-calibrated camera on the basis of the three-dimensional coordinates of the obtained characteristic points as well as pixel coordinate information of the obtained characteristic points in an image corresponding to the to-be-calibrated camera, and acquiring new parameters of the to-be-calibrated camera.