Patent ID: 7206014

Claim:
A multi-beam scanning apparatus, comprising: at least two light source sections each including a pair of semiconductor laser diodes and coupling lenses, said coupling lenses coupling respective light beams irradiated from the pair of semiconductor laser diodes, and each of said at least two light source sections being configured to rotate independently; a holding member configured to hold the at least two light source sections and to rotate each of the at least two light source sections together; a light beam-approximating device configured to approximate a pair of light beams irradiated from the pair of semi-conductor laser diodes; a scanning device configured to diffuse and scan a scan receiving surface with the pair of light beams in a spot shape; a beam pitch detecting device configured to respectively detect a beam pitch between beam spots formed by the pair of light beams irradiated from the laser diodes on the scan receiving surface; and a beam pitch correcting device configured to initially correct the beam pitch by automatically rotating at least one of the two light source sections around an optical axis and to secondly adjust a distance between points C 1 and C 2 by automatically rotating the holding member, wherein C 1 is a virtual middle position between beam spots created by the pair of light beams irradiated from the pair of semi-conductor laser diodes in a first of the at least two light source sections, C 2 is a virtual middle position between beam spots created by the pair of light beams irradiated from the pair of semi-conductor laser diodes in a second of the at least two light source sections, a distance between beams spots included in a same pair of beam spots in a main-scanning direction is shorter than a distance between corresponding beam spots in different pairs of beam spots in the main-scanning direction, and the at least two light source sections are arranged in the main-scanning direction and the pair of semiconductor laser diodes are arranged in a sub-scanning direction.