New principle of rangefinding using blurred images

Abstract

Basic principles are established for a method of obtaining range data by measuring the profile of blurs in or near the back focal plane of a lens or lens system resulting from the capture of light from a point or line source situated on an object in the scene. The effectiveness of the method is demonstrated using simulation and practical means. It is suggested that the principle could form the basis of a rangefinder for robotic applications in which objects are illuminated by a coaxial laser projector with the reflected light being captured by an aperture-restricted lens system.