Image forming apparatus

An image forming apparatus including a rotating photosensitive drum, the image forming apparatus being capable of performing a first mode in which the photosensitive drum is rotated at a first rotating speed and a second mode in which the photosensitive drum is rotated at a second rotating speed lower than the first rotating speed, the image forming apparatus comprising:

• an exposure head including light-emitting rows each of which includes light-emitting portions configured to emit light for exposing the photosensitive drum, the light-emitting portions being arranged along a rotational axis direction of the photosensitive drum, the light-emitting rows being arranged in a direction crossing the rotational axis direction, the exposure head being configured to multiply expose regions each of which corresponds to one pixel on the photosensitive drum with light-emitting portions included in a plurality of rows out of the light-emitting rows;
• and
• a control unit configured to control the light-emitting portions such that each region of the regions is multiply exposed by light-emitting portions included in a plurality of rows out of the light-emitting rows, and such that the number of a plurality of rows of light-emitting portions that emit light for multiply exposing the each region in the first mode is greater than that in the second mode.