Detection device

A detection device comprising:

• a plurality of photodiodes configured to detect information on an object to be detected in a detection area during a predetermined detection period;
• a power supply control circuit configured to individually control a reverse bias voltage applied to each of the photodiodes;
• and
• a plurality of power supply circuits configured to supply, to each of the photodiodes, a first potential at which the reverse bias voltage is set to a first voltage or a second potential at which the reverse bias voltage is set to a second voltage lower than the first voltage, based on a control signal from the power supply control circuit,
• wherein the photodiodes are respectively provided for a plurality of partial detection areas of the detection area, and
• wherein the power supply control circuit is configured to:
• detect an output level of a signal output from each of the partial detection areas when the first potential is supplied to the photodiodes during a setting period different from the detection period, and
• control the power supply circuits so as to supply the second potential to the photodiode of the partial detection area in which the output level of the signal is equal to or higher than a predetermined threshold during the detection period.