A simple and accurate camera-sensor calibration for surgical endoscopes and microscopes

Abstract

Nowadays, augmented reality (AR) has become a key technology for surgical navigation. It is necessary to perform camera-sensor calibration to build AR between a camera and a sensor that tracks the camera. In order to perform camera-sensor calibration, it has been common method to move the camera in such a way as to solve an AX = XB type formula. However, in clinical environments, Endoscopes and microscopes are commonly used, and moving those cameras is very difficult due to their large weight and size when camerasensor calibration is performed. Therefore, we propose a method to solve the camera-sensor matrix by expanding the AX = XB equation to the AX = BYC equation. Instead of moving the camera, we move the calibration pattern in the proposed method. Through the experiments, we compared the AX = BYC solution with the AX = XB solution in terms of the accuracy. As a result, we found the proposed method is more convenient and accurate than the conventional method.