Patent ID: 9274154
Filing Date: 2016-03-01
CPC Classification: G01R,H03K

Claim Text:
1. An electrostatic capacitance sensor comprising: a detection electrode that detects an electrostatic capacitance between the detection electrode and an object; a shield electrode that is disposed in vicinity of the detection electrode; a shield drive means that switches between a first electric potential and a second electric potential different from the first electric potential to apply the first or second electric potential to the shield electrode, wherein the first electric potential and the second electric potential are different from a ground potential, and the shield drive means is connected to the shield electrode; a detection means that outputs a detection signal depending on the electrostatic capacitance detected by the detection electrode, wherein the detection means is connected to the detection electrode; and a determination means that obtains a first detection signal and a second detection signal from the detection means as a basis to determine whether an abnormality of the detection electrode and/or the shield electrode is present or absent, the first detection signal depending on the electrostatic capacitance detected by the detection electrode when the shield drive means applies the first electric potential to the shield electrode, the second detection signal depending on the electrostatic capacitance detected by the detection electrode when the shield drive means applies the second electric potential to the shield electrode.