Abstract: A system and method for compensating pixel values in an inspection machine for inspecting printed circuit boards includes an image acquisition system for providing pixel values from a digitized image to a compensation circuit. The compensation circuit applies one or more compensation values to the digitized pixel values to provide compensated digitized pixel values for storage in a memory. The compensated digitized pixel values are then available for use by an image processor which implements inspection techniques during a printed circuit board manufacturing process. With this technique, the system corrects the errors on a pixel by pixel basis as the pixel values representing an image of a printed circuit board are transferred from the image acquisition system to the memory.
Abstract: A thermally efficient circuit board has a base layer with high thermal conductivity and a thermal expansion coefficient close to that of silicon, such as aluminum silicon carbide. Above the base layer is a layer of anodized metal, either a separate material, such as aluminum, which is formed on the base and then anodized, or an anodized portion of the base itself. To the anodized metal is then applied a sealant material of lower thermal conductivity, but good electrically insulative and adhesive qualities, such as Teflon FEP. The sealant flows into cavities in the porous anodized metal structure, creating a well-anchored bond. A metal foil layer is then bonded to the surface of the sealant, and used to pattern conductive circuit paths using conventional methods.