A new eddy current probe using uniform rotating eddy currents

A new eddy current probe has been devised using uniform rotating eddy currents and a pancake pick-up coil. The self-differential feature makes the probe self-nulling and free of lift-off noise. The self-differential feature of the probe also minimizes effects from variations in electromagnetic characteristics and configurations of test materials. Another feature of the probe is that it generates different anomaly signal patterns depending on the anomaly direction. The newly developed probe is a reliable one with less noise and more information on anomalies than conventional probes.