Gap sensor and gap measuring method using a capacitance measuring technique detecting or measuring gaps between conductive member surfaces

摘要

A probe is a three-layer substrate having two faces on which paired electrodes are formed at corresponding positions and guard patterns are formed around the electrodes. The guard patterns and all electrodes are driven by a common probe signal to an equal potential, thereby commonly guarding the electrodes. Based on a clamp current of each electrode, a capacitance is found to obtain gap data.