US Patent 11599222 Detection device

This detection device includes a sensor electrode, a shield electrode, which has a parasitic capacitance between the sensor electrode and the shield electrode and is driven by an AC voltage, a detection circuit, which is electrically connected to the sensor electrode and the shield electrode and detects the electrostatic capacitance of the sensor electrode, a capacitor, which is connected in series between the sensor electrode and the detection circuit, and a bias unit, which biases the potential of the sensor electrode via a resistor.