Optical scanning device and image forming apparatus

An optical scanning device, comprising:

• a photoreceptor on which a latent image is formed by scanning thereof with a laser beam, a scanning position of the laser beam being divided into a plurality of areas aligned in a main scanning direction;
• a light source unit which outputs the laser beam, the photoreceptor being scanned in the main scanning direction with the laser beam;
• a plurality of correction value storage units, each of which stores a light quantity correction value that is predetermined in association with each of the areas;
• and
• a light quantity correction unit which corrects a light quantity when scanning the photoreceptor with the laser beam by using the light quantity correction value stored in the correction value storage unit in association with each of the areas corresponding to the scanning position of the laser beam, wherein
• a target correction amount for correcting the light quantity is predetermined according to a position of the photoreceptor in the main scanning direction, and the target correction amount changes according to the position of the photoreceptor in the main scanning direction,
• a length, in the main scanning direction, of each area contained in the plurality of areas is shorter in an area in which a correction value change rate, which is a variation in the target correction amount per unit length of the main scanning direction, is greater, and
• the light quantity correction value is determined based on the target correction amount according to a position of an area corresponding to the light quantity correction value.