Three-dimensional object recognition by Fourier transform profilometry

An automatic method for three-dimensional (3-D) shape recognition is propos ed. It combines: the Fourier transform profilometry technique with a real-t ime recognition setup such as the joint transform correlator (STC). A grati ng is projected onto the object surface resulting in a distorted grating pa ttern. Since this pattern carries information about the depth and the shape of the object, their comparison provides a method for recognizing 3-D obje cts in real time. A two-cycle JTC is used for this purpose. Experimental re sults demonstrate the theory and show the utility of the new proposed metho d. (C) 1999 Optical Society of America.