Patent ID: 8619058

Claim:
An electrostatic capacity type touch sensor, comprising: a substrate; a first common electric potential line disposed on the substrate; a second common electric potential line disposed on the substrate, the second common electric potential line surrounding the first common electric potential line; first and second detection electrodes disposed on the substrate in a region interposed between the first and second common electric potential lines and being axisymmetrical with respect to a Y axis, the Y axis intersecting a common center of the first and second common electric potential lines; third and fourth detection electrodes disposed on the substrate in the region and being axisymmetrical with respect to an X axis, the X axis intersecting the common center and being orthogonal to the Y axis; a charge amplifier generating a first output voltage and a second output voltage, the first output voltage being proportional to a capacitance difference between a capacitance of a first capacitor formed between the first detection electrode and the first and second common electric potential lines and a capacitance of a second capacitor formed between the second detection electrode and the first and second common electric potential lines, the second output voltage being proportional to a capacitance difference between a capacitance of a third capacitor formed between the third detection electrode and the first and second common electric potential lines and a capacitance of a fourth capacitor formed between the fourth detection electrode and the first and second common electric potential lines; first to fourth terminals electrically connected to the first to fourth detection electrodes, respectively, for applying the charge amplifier with voltages corresponding respectively to the capacitance of the first capacitor, the capacitance of the second capacitor, the capacitance of the third capacitor, and the capacitance of the fourth capacitor, the first to fourth terminals being included a first wiring layer; and a common electric potential line electrically connecting the first common electric potential line and the second common electric potential line, the common electric potential line being included in a second wiring layer different from the first wiring layer, the common electric potential line electrically isolated from and overlapping the first detection electrode in a plan view of the electrostatic capacity type touch sensor.