Binarization of scanning Moiré fringe pattern

This paper describes a digital picture processing method to obtain a binary scanning moiré pattern. In this method, a bias component due to the illumination light distribution is eliminated from the scanning moiré fringe pattern to detect the zero-crossing points of the moiré profile. The binary fringe pattern is then obtained from the zero-crossing points. Experiments indicate that the method is useful for facilitating three-dimensional automatic measurement using moiré topography.