Characteristics of Inspecting Signals Depending on Shapes of Defects Using Eddy-Current Testing Probe.

Eddy-current testing (ECT) is a non-destructive inspection method having various advantages, such as testing that involves both conduction and non-contact. One attractive application for ECT is inspection for etching defects in high-density printed-circuit boards (PCBs). To apply the ECT technique to PCBs, it is important not only to make a conformable probe but also to investigate the characteristics of signals using the probe to determine the shapes of defects. This paper describes characteristics of inspecting signals for shapes of defects. When resultant signals are expressed in two dimensions, we can clearly examine etching defects in PCBs.