An image signal output unit is controlled in accordance with a first control signal indicating either voltage state of an on voltage for causing a conductive state and an off voltage having a polarity different from that of the on voltage, and outputs an analog image signal corresponding to the electric charge held by an electric charge holding unit in the conductive state. A reset unit is controlled in accordance with a second control signal indicating either voltage state of the on voltage and the off voltage, resets the electric charge holding unit in the conductive state, transmits a fluctuation in the off voltage to the electric charge holding unit, and fluctuates the analog image signal. A reference signal generation unit generates a reference signal being a signal serving as a reference used when conversion from an analog image signal output from the image signal output unit into a digital image signal is performed. A reference signal correction unit corrects the generated reference signal in accordance with the fluctuation in the off voltage. An analog-to-digital conversion unit performs the conversion on the basis of the corrected reference signal.