Automated radiographic inspection of through-hole electronic circuit board solder defects

Abstract

A study has been carried out to investigate the use of "real-time" radiography as a method of automated inspection of through-hole electronic circuit board solder joints. By evaluating five major solder defects it has been found that film radiography employing high contrast film results in a definite distinction between a good solder joint and a defective solder joint. The same five defects were also found to be distinguishable from a good solder joint when evaluated by a real-time radiographic inspection unit using digital image processing. Although the type of defect being investigated was not discernible, the ability to distinguish a good solder joint from a defective solder joint is a major step in the implementation of automated solder joint inspection for military electronics.