Electromagnetic imaging using probe arrays

摘要

Electromagnetic methods like eddy current technique do not provide images but only produce local signals in a difficult to understand measurement plane. Filters, thresholds and phase rotators are common tools of signal processing unable to bring up all information contained in the signals. Trials to generate images comparable to x-rays mostly base on costly and time consuming mechanical surface scanning. The paper presents theoretical and experimental steps ahead to modular 1D, 2D and 3D probe arrays for eddy current inspection. In contrary to other attempts these arrays work at low frequencies able to penetrate below the surface and provide good lateral resolution. That way they bring up not only surface but also hidden defects and anomalies. Potential applications are outlined.