Applying a ray tracing model of an optoelectronic system to improve the accuracy of endoscopic measurements

Abstract

The problem of improving the accuracy and extending the range of geometrical measurements taken by video endoscopes equipped with attachable stereo adapter has been considered. For calibration and measurements, it has been suggested to use a ray tracing model of stereoscopic recording that takes the actual paths of rays in the prism into account. Based upon multiple experiments with test objects, it has been shown that this allows one to reduce the error in measurements of linear dimensions (length and depth) and area. The theoretical conclusions have been confirmed by results obtained when measuring defects in the blades of a jet engine with the use of a real stereoscopic video-endoscopic system.