Patent ID: 6933732

Claim:
A capacitance type sensor comprising: a substrate; a displaceable detective member facing the substrate; a conductive member disposed between the substrate and the detective member, wherein the conductive member is displaceable in a direction perpendicular to a plane of the substrate in accordance with displacement of the detective member; a reference electrode disposed on the substrate and electrically connected with the conductive member, wherein the reference electrode is at a predetermined electric potential; a first electrode disposed on the substrate; a second electrode disposed on the substrate to constitute a first capacitance element with the conductive member; and a third electrode electrically connected with the second electrode, wherein the third electrode is contactable with the first electrode, elastically deforming in accordance with displacement of the conductive member, and wherein, when the first electrode and the third electrode are in contact with each other a signal input to the first electrode is used to identify the displacement of the detective member on the basis of changes in capacitance of the first capacitance element caused by changes in distances between the conductive member and the second electrode.