Abstract: An optical unit for inspecting the soldered surface of a printed circuit board incorporates a thick-walled translucent concave diffuser dome with a hollow central cavity facing the surface under inspection, lamps directing illumination on the exterior of the dome, inspection portals spaced around the diffuser dome for video camera inspection of the board surface, and X-Y maneuvering control means governing the relative scanning repositioning of the board surface and the dome. A light baffle between each camera and its inspection portal, incorporating alternately white and black conically chamfered rings, produces improved imaging of the inspected surface, and a flexible translucent skirt extending from the dome rim to the inspected surface, preferably formed of a large plurality of white plastic bristles, blocks direct illumination and assures substantially uniform diffused illumination of the inspected surface.

Abstract: Visual guidance methods and apparatus are provided for directing the treatment of workpieces, such as the assembly of printed circuit boards, by providing a full-size optical image of each successive treatment step in turn, superimposed on the operator's actual view of the workpiece itself. The workpiece is viewed through a half-silvered mirror which also delivers an image of a programmed mylar film with instructional steps and parts shown as full-size partial images superimposed on the operator's view of the workpiece itself. Simultaneous actuation of parts storage bin trays automatically delivers the required parts for each assembly step. Indexing of the apparatus moves the mylar film to exhibit the next treatment step, aligned with the workpiece, by index code indicia accompanying each partial image to be superimposed on the view of the workpiece, and simultaneously exposes the next parts storage bin for delivery of the next required component part to the operator.