Optical surface height measurement procedure lights it from two sources with different light types and path lengths combined to the same incidence angle

摘要

A optical surface height measurement procedure lights (1, 2) it from two sources successively with different light types as the surface and instrument move relative to each other so as to examine it with different optical path lengths (4) at similar incidence angles to and compares the brightness values (5) obtained. Independent claims are included for optical surface height measurement equipment using the procedure.