Detection device

A detection device comprising:

• an optical sensor having a detection area in which a plurality of sensor pixels are arranged in a planar configuration;
• a light source in which a plurality of light-emitting diodes are arranged in a plane parallel to the detection area;
• and
• a control circuit configured to control the optical sensor and the light source, acquire detection values of the sensor pixels, and generate an image of an object to be detected placed in the detection area, wherein
• each of the sensor pixels is associated with a nearest light-emitting diode of the light-emitting diodes, and
• the control circuit is configured to acquire detection values of the sensor pixels when the object to be detected is not placed in the detection area, and uniformly set current set values of the light-emitting diodes so that an average value of the detection values of the sensor pixels associated with the light-emitting diodes that are not failed falls within a target range.