I/O pin solder-point inspection system

We have developed an automated inspection system that features perpendicular and variable- intensity lighting for image contrast enhancement and improved sensing accuracy, a high- resolution camera with reflection-adaptive binarization for improved image processing, and an adaptive inspection algorithm that modifies its defect definition criteria according to target position quickly, accurately, and reliably inspects highly dense arrays of perpendicular I/O pins soldered onto a ceramic printed wiring board (PWB). The system's Mega-Scope, a high- resolution, eight-bit gray-scale CCD camera, images a 2048 X 2048-pixel area with a 10 micrometers resolution in 4 seconds, taking 60 I/O pin images at a time. The total time to inspect the position and solder fillet condition of more than eight thousand I/O pins is just 30 minutes.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.