Patent ID: 8922847

Claim:
An image forming apparatus comprising an optical scanning apparatus and a correction unit, the optical scanning apparatus including: a light source including a plurality of light emitting elements each configured to output, based on input image data, a light beam for irradiation of a photosensitive member driven to rotate, wherein the plurality of light emitting elements are arranged so that the photosensitive member is irradiated at different positions in a rotational direction with a plurality of the light beams output from the plurality of light emitting elements, a deflection unit provided in the optical scanning apparatus and configured to deflect the plurality of light beams output from the plurality of light emitting elements so that the plurality of light beams scan on the photosensitive member, a lens provided in the optical scanning apparatus and configured to guide the plurality of light beams deflected by the deflection unit to the photosensitive member, and a temperature detecting unit configured to detect an internal temperature of the optical scanning apparatus; the correction unit being configured to correct a scanning width of at least one of the plurality of light beams emitted from the plurality of light emitting elements based on the input image data, based on a result of the detection by the temperature detecting unit, so that the plurality of light beams output from the plurality of light emitting elements based on the input image data have the same scanning width in a scanning direction in which the plurality of light beams scan on the photosensitive member.