Optical scanning device and image forming apparatus

Abstract

There is provided an optical scanning device and an image forming apparatus including the optical scanning device. The optical scanning device includes an optical box containing light source units, a rotating polygon mirror, and a motor. In order to prevent the entire optical box from being deformed by deformation occurring in the installation region due to heat of the driving unit, the optical box includes a connection region between a second sidewall and an installation region where a driving unit is installed. The optical box further includes regions provided next to the connection region and having heights different from each other. A concave portion is formed in the connection region.

What is claimed is: 
     
         1 . An optical scanning device comprising:
 a deflection unit including:   a rotating polygon mirror configured to deflect a first light beam emitted from a first light source and a second light beam emitted from a second light source, such that the first light beam scans a first photosensitive member and the second beam scans a second photosensitive member, wherein the rotating polygon mirror is configured to deflect the first light beam and the second light beam in respective directions opposite to each other in respect to the rotating polygon mirror;   a motor configured to cause the rotating polygon mirror to rotate; and   a driving unit configured to drive the motor;   a first reflection mirror configured to guide the first light beam deflected by the rotating polygon mirror, onto the first photosensitive member;   a second reflection mirror configured to guide the second light beam deflected by the rotating polygon mirror, onto the second photosensitive member; and   an optical box including a bottom, to which the deflection unit, the first reflection mirror, and the second reflection mirror are attached, and sidewalls standing from the bottom and to which the first light source and the second light source are attached,   wherein the bottom includes a wave-shaped bottom having a wave shape in cross section in a scanning direction of the both light beams deflected by the rotating polygon mirror, and the wave-shaped bottom is provided in a region surrounded by one of the sidewalls located opposite a light path of each of the first light beam and the second light beam that are incident on the rotating polygon mirror in the scanning direction, the deflection unit, the first reflection mirror, and the second reflection mirror.