As an application of eddy-current testing (ECT) technique, the inspection of printed circuit board (PCB) using ECT probe has been proposed, and for the actual acquisition of the existence and position of the defect, analyzing methods of ECT images have been also investigated. In those approaches, one important theme is the removal of undesired components contained in images, which disturb correct data analysis. This paper describes an image processing method for this aim using multiresolution analysis. Since filters used in this method have a linear phase, the waveforms of signals are maintained in each subband, which results in a correct manipulation about amplitude. The ability of the method to extract defect signal in undesired signals is shown through analysis of ECT images derived from samples for benchmark test and PCBs.
展开▼
