| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a position detection device capable of grasping a physical quantity equivalent to an electrostatic capacitance value and easily detecting the position of a movable electrode.SOLUTION: The position detection device comprises: a switch unit 160 for switching between a grounded state and a floating state of a movable electrode 120 with respect to ground; and a control unit 175 for controlling the switching between the grounded state and the floating state by the switch unit (160), grasps, for each of a plurality of fixed electrodes 141 and 142, composite capacitances CHton, CHtoff, CLton and CLtoff including inter-electrode capacitances CH and CL, switch capacitances CDon and CDoff in the switch unit 160, and parasitic capacitances CHp and CLp occurring in each of the plurality of fixed electrodes 141 and 142, and calculates, from differencesΔCH andΔCL in the composite capacitances at the time of the grounded state and at the time of the floating state, respective capacitances equivalent to the inter-electrode capacitances CH and CL.</p> |
