Notch inspection apparatus and method based on shading pattern matching

摘要

A notch inspection method based on shading pattern matching for inspecting notches on semiconductor packages or like objects. A template is created to characteristically express brightness gradations of a notch edge in a picture, i.e., to represent the notch edge in pixels constituting contiguous bright and dark portions of the edge. The template may be created on the basis of notch size information or notch size measurements. The template is checked against pictures under inspection in shading pattern matching whereby presence of a notch is determined. Computations of shading pattern matching are omitted regarding portions of the notch edge where brightness remains unchanged.