The present invention relates to an image processor that is configured to compare a single frame included in the received signal with a preceding processed frame so as to detect changes. The first aspect of the present invention is a contamination inspection device comprising: an irradiation optical system for irradiating lights on the inspection target substrate; and a spatial filter for shading diffracted lights form the inspection target substrate. The first backplate unit comprises a first backplate body and a plurality of first upper hooks. More complicated embodiments of the present invention include additional transistor rows in the stack with isolated Nwells and Pwells.