Patent US 6,777,677

A pattern inspection system for inspecting a substrate surface on which a predetermined pattern is formed with radiation of an electron beam and an optical beam. the pattern inspection system includes a radiation and which radiates an electron beam to the substrate, a detection unit which detects a secondarily generated signal attributable to the radiation of the electron beam, a retrieval unit which retrieves an image from the signal detected by the detection unit, and an image processing unit which classifies the retrieved image depending on a type of the image.