A detection device includes a plurality of detection units formed on a semiconductor circuit, a correction capacitive element that indicates a correction capacitance value for correcting detected capacitance values detected by the detection units, a difference acquisition circuit that acquires a difference value between each of the detected capacitance values and the correction capacitance value, and a conversion circuit that converts the difference value into a digital signal. The correction capacitive element, the difference acquisition circuit, and the conversion circuit are formed on the semiconductor circuit.