Fast 3D in-line sensor for specular and diffuse surfaces combining the chromatic confocal and triangulation principle

Abstract

Fast 3D sensors for 100% in-line quality control are rare. Heavy demands on speed exclude most of the available measurement devices. This article introduces a new measurement principle for this purpose, combining the chromatic confocal and the triangulation principle. The result is an optical line scan measurement device that measures the 3D topology of specular and diffuse surfaces in absolute coordinates. The sensor system consists of an optical design, optimized optical filters, and a multi channel line scan camera. The filters are derived using information and coding theory and a proposed physical motivated color space transformation.