Patent ID: 8330784

Claim:
An image forming apparatus comprising: a plurality of developers; and optical scanners, each of the optical scanners comprising a light source and a light reflecting unit and forming an electrostatic latent image on a photo conductor of each of the developers, wherein the optical scanners have the same focusing distance from the light source to the photo conductor, the light reflecting unit of one of the optical scanners is arranged at a position different from the light reflecting unit of another optical scanner, such that intervals between the developers vary, the plurality of developers comprise a yellow (Y) developer, a magenta (M) developer, a cyan (C) developer, and a black (K) developer, the optical scanners comprise a first optical scanner, which forms electrostatic latent images on two of the developers including the black (K) developer, and a second optical scanner, which forms electrostatic latent images on the other two developers, each of the light reflecting units of the first and second optical scanners have a polygonal mirror unit, which rotates and reflects light emitted by the light source in a direction corresponding to a main scanning direction of the photo conductor, a rotating axis of the polygonal mirror unit of the second optical scanner is tilted by a predetermined angle θ, and an interval between the two of the developers including the black (K) developer is wider than an interval between the other developers.