摘要 |
A capacitance type sensor includes a detection electrode, a reference electrode, and a sub-reference electrode for distinguishingly detecting a detection object. The sub-reference electrode has a reference voltage applied thereto and is displaceable relative to the detection electrode due to a pressure exerted from the detection object. A voltage application device applies a detection voltage to form an electric field in a space defined with the reference electrode device. A capacitance detector of the sensor detects a first capacitance and a second capacitance, and a detection unit of the sensor distinguishingly detects the detection object based on the first capacitance and the second capacitance. The first capacitance is measured between the detection electrode and the reference electrode, and the second capacitance is measured between the detection electrode and the sub-reference electrode.
|