Image forming apparatus

An image forming apparatus comprising:

• an exposing unit including:
• a first light source comprising:
• a first light emitter;
• and
• a first light receiver including a first electric output responsive to a received light quantity of the first light emitter;
• a second light source comprising:
• a second light emitter;
• and
• a second light receiver including a second electric output responsive to a received light quantity of the second light emitter;
• and
• a first light-source driver electrically connected to the first light source and the second light source, the first light-source driver including:
• a first output terminal electrically connected to the first light emitter;
• a second output terminal electrically connected to the second light emitter;
• and
• an input terminal electrically connected to both the first electric output and the second electric output;
• and
• a controller communicatively connected to the exposing unit and programmed to provide an exposing operation instruction to the first light-source driver.