LIGHT SOURCE DEVICE AND OPTICAL SCANNING APPARATUS USING THE SAME, IMAGE FORMING DEVICE

PROBLEM TO BE SOLVED: To provide a light source device with less spot position variation of a sub-scanning direction, and to provide an optical scanning apparatus having a small amount of light volume loss. SOLUTION: A holder of each light source/optical element unit 32a and 32b includes a cylindrical part housing a lens barrel in its inside, and a pushing means for pushing the lens barrel in an inner face of the cylindrical part for fixing. The pushing means is arranged in an optical scanning face of the light source device at a position orthogonal to an optical axis of the optical element, furthermore, mounts a slit at a place apart from the optical element only by a focal distance of the optical element, and the magnification of the sub-scanning direction of the optical system in the optical scanning apparatus is Q/P when a variation of the sub-scanning direction of two light sources of the light source device is P and an allowable range of the spot position variation of the sub-scanning direction of two light sources on a medium to be scanned is Q. COPYRIGHT: (C)2008,JPO&INPIT