Solid solders
A reliable method for detecting soldering errors on circuit boards has been developed by the heavy industries division of Mitsubishi in Japan. Three perpendicular laser beams just five micrometers wide are fired at the solder tracks, sending three-dimensional data to a microprocessor. The shape of each track - especially the adhesion angle and height - is assessed to decide whether the sol- der is good or defective. The method is 10 times more reliable than existing automated systems (New ScientisA Vol 160, No 2160).