I/O Pin Solder Point Inspection System

Abstract

We have developed an automated inspection system that features perpendicular and variable-intensity lighting for image c o n a t enhancement and improved sensing accuracy a high-resolution camera with reflection-adaptive b i n d t i o n for improved image processing, and an adaptive inspection algorithm that modifies its defect definition criteria according to target position quickly, accurately, and reliably inspect highly dense arrays of perpendicular I/O pins soldered onto a ceramic printed wiring board (PWB). The system's Mega-Scope, a highresolution, eight-bit gray-scale CCD camera, images a 2048x2048-pixel area with a 10 pm resolution in 4 seconds, taking 60 U0 pin images at a time. The total time to inspect the position and solder fillet condition of more than eight thousand U0 pins is just U) minutes.