Abstract: Image processing elements forming an image processor for automatic inspection of circuits. Each processing element for performing a thinning algorithm passes along a data bit and a flag bit to each succeeding processing element. The flag bits permit a conditional deletion of a data bit. Within each processing element a feedback bit is used to indicate when a previous bit has been deleted. The skeletonized image is reviewed for identification of circuit geometries and counting the number of separate blobs. A report is generated in response to the identified geometry and blob count.

Abstract: An apparatus for automatic printed wiring board (PWB) defect detection comprises an array of optical sensors for optically inspecting a printed wire circuit. The array forms a binary image pattern of the PWB which is tested for compliance with logical rules of correctly printed PWB's regarding unterminated conductors; a set of minimum and maximum specified line widths; line spacing width; presence of insulators on conductors and vice versa; presence of pinholes, flecks of copper, and Vees and neck-downs.A method employs an inner enable pattern of pixel bits formed to determine if a feature being viewed is possibly on a conductor line or insulator space. A set of same-state patterns is formed around the center of the matrix with each pattern being progressively larger. The state of opposite pixel points on the same-state patterns is progressively examined to determine the first inner pattern in which opposite pixel points are ot in the same state.

Abstract: An isotropic light source produces uniform illumination of a generally planar objects to be visually inspected by a microscope such as a P.C. board having an irregular specular surface. Detrimental dark spots which are normally produced are eliminated by providing a skewed beamsplitter between the microscope and the viewed surface, which beamsplitter redirects light directly at the object along or near the optical viewing axis. The isotropic light source is a light integrating cavity in a first embodiment and a pair of fluorescent lamps in a second embodiment.