Surface profiling and imaging system including optical channels providing distance-dependent image offsets

Abstract

A surface profiling system is provided including an imaging detector array and an optical imaging array comprising at least one set of optical channels. Each optical channel includes a lens arrangement (e.g., including a GRIN lens) configured to provide an erect image at a detector. The optical channels have overlapping fields of view (FOV) and overlapping imaged fields of view (IFOV). A workpiece surface point may be simultaneously imaged in at least two overlapping IFOVs of two optical channels. A surface point that is not at an object reference distance (e.g., a front focal length) may be imaged at different respective positions along the imaging detector array, and the difference between the respective positions may define a respective image offset for that surface point. A surface height measurement coordinate for the surface point may be determined based on the corresponding image offset.