LASER SCANNING OPTICAL DEVICE

摘要

PROBLEM TO BE SOLVED: To obtain a laser scanning optical device, with which miniaturization of an image forming apparatus can be achieved, by eliminating wasteful space formed in between the device and an image forming unit, in a tandem system. SOLUTION: In the laser scanning optical device, a plurality of beams BY, BM, BC, BK deflected by a single polygon mirror 5 are exposed onto respective photoreceptor drums 11Y, 11M, 11C, 11K via a scanning optical system 20. The scanning optical system is constituted of a first scanning lens 21 through which all beams pass through, respective second scanning lenses 22Y, 22M, 22C, 22K corresponding to respective beams, and a flat mirror for folding back the optical path. The distance between each of the second scanning lenses and each of the corresponding photoreceptor drums is set with relation: Ly=Lm=Lc