Discrimination of Spatially Confused Beams for Ranging with Single Camera

It has been demonstrated that multiple beam ranging can be achieved with a single camera and a spatially encoded probing beam matrix. However, as the density of the beam matrix increases, identification ambiguities among some of the probing beams may occur that will cause errors in triangulation ranging. This paper focuses on how to label the beams that are otherwise confused by the spatial encoding. An optimized system configuration is constructed to create unique regions in the image plane to enhance the probing beam identification. If needed, further discrimination is achieved using boundary conditions and adaptive thresholds. The system is demonstrated with 7×7 probing beams and a VGA CMOS camera.