A touch panel capable of calculating touch position coordinates of an indicator with high accuracy in a desired detection time even if a large number of detection wire groups are provided. An oscillator circuit selects one of detection wires and selected by a circuit or the like according to a command from a detection control circuit and oscillates. A circuit counts an output signal from the oscillator circuit up to a first count value. A circuit measures a period of the count. A circuit determines that there is a touch when it detects the detection wire of which the measured period is equal to or higher than a threshold value and sends the detection wire giving a maximum value equal to or higher than the threshold value to a circuit as a touch detection wire. The circuit causes the circuit or the like to select the touch detection wire and the detection wires adjacent thereto on both sides, the circuit counts up until the count value becomes a second count value larger than the first count value, and the circuit measures the count period. The circuit performs interpolation on the basis of the count value obtained by subtracting a background capacitance value from a measured value obtained by the circuit, to thereby determine the touch coordinates.