|A sheet (P) processing apparatus (1) and method, the apparatus comprising a thickness detecting device (100), the thickness detecting device including: |
a plurality of conductive displacement members (220) configured to be displaced depending on the thickness of the sheet (P);
a plurality of resonance circuits (210) that are disposed to correspond to the plurality of displacement members (220), each including a coil (204) facing the corresponding displacement member (220) and a capacitor (208), where neighboring resonance circuits resonate at different resonance frequencies;
means for detecting the distance between the displacement members and their associated resonance circuits based on impedance values of the plurality of resonance circuits and the plurality of displacement members;
a calculation unit (240) that calculates a thickness of the sheet based on the distance values, and therefore on impedance values of the plurality of resonance circuits and the plurality of displacement members.