抄録
The shape of a magnetic body was detected with measurement of the magnetic field distribution using the hall sensor. Test specimens with a step on the backside were measured and, the magnetic flux of the experiment was compared with the analysis. The experiment and the analysis showed a similar tendency, and differences in the thickness of the specimen were detected. But sensitivity of detection was not improved by using the magnetic lens. Results will the presented the experiment and the analysis in the case of different shape of the magnetic lens.