Abstract

This patent describes a mechano-optical non-contact system, and method of use, for characterizing the topography of an area of a surface. The instrumentation consists of an optical system that illuminates a small region of the surface with a focused wedge of light at fixed angle, a magnification system to view the diffuse reflected profile image, a video camera that provides electrical signals corresponding to the profile image, a three dimensional, computer controlled motorized stage, a means for automatically focusing each region of the surface with respect to the optical system, and a computer to analyze and operate on the signal, and record the primary topographical data. The primary data obtained, from which all other parameters derive, are the heights, over an area, as a function of their x,y coordinates in a reference plane (i.e. z(x,y)). The system automatically measures the coordinates of points on the surface, at equally spaced intervals, along profiles that can be many times the optical field. Coordinate data for an area are obtained by measuring the coordinates along close and equally spaced profiles within the region.