| 摘要 |
<p>The disclosure has: a detection electrode (2) that detects an electrostatic capacitance; a shield electrode (3); a shield drive circuit (31) that switches between a first electric potential and a second electric potential to apply the first or second electric potential to the shield electrode; a detection circuit (21) that outputs a detection signal depending on the electrostatic capacitance detected; and a determination circuit (6) that obtains a first detection signal and a second detection signal as the basis to determine whether an abnormality of the detection electrode (2) or the shield electrode is present or absent. The first detection signal depends on the electrostatic capacitance detected when the shield drive means (31) applies the first electric potential to the shield electrode (3). The second detection signal depends on the electrostatic capacitance detected when the shield drive means (31) applies the second electric potential to the shield electrode.</p> |
