ABSTRACT
Optical profilometry measurement [1–8], an efficient tool in scientific, industrial, medical and other applications, has been extensively studied. In most of the applications, a structured pattern, such as a spot, single line or grating is projected onto the surface to be measured and the distorted pattern caused by the depth variation of the surface is recorded by a CCD camera at an angle to the illumination direction. This is optical triangular profilometry. On the basis of different structured light illuminations, optical triangular profilometry is classified under three types: spot inspection, a single-line system or a projection grating system. Although the configurations of three types are quite different, their distance mapping algorithms [10–12] between depth variation and deformed signal are inherently the same. The ray tracing can start from either the projection or image ray.
