Compact vision using circular dynamic stereoscopy with a beam splitter

Circular dynamic stereoscopy (CDS) has special advantages for 3-D measurement as it uses a single CCD camera without cumbersome settings. In CDS, annular streaks are recorded, with their size inversely proportional to the depth/distance of the measuring point from the CCD camera. Therefore three-dimensional information can be measured automatically by image processing techniques. When the measuring points are relatively dense, streaks on the image plane overlap, making automatic processing difficult. To cope with this problem, one of the coupled mirrors is replaced by a beam splitter. The annular streaks and their corresponding center positions are then recorded on the same image as the displacement. The recording of the center positions helps in resolving the overlapping annular streaks.