| 摘要 |
<p>PURPOSE:To decrease the rotating speed of a rotary polygon mirror and the scanning speed of a laser beam on the exposure surface of a photosensitive body, etc., by providing plural laser light sources and providing a means which forms plural different main scanning lines simultaneously by performing a laser besm scan on the exposure surface only once. CONSTITUTION:Image electric signals at the same subscanning positions among signals stored in a memory 8 are transferred to the 1st and the 2nd modulatng means 71 and 72 at the same time. Then the 1st and the 2nd laser light sources 11 and 12 output laser light modulated according to the image electric signals. The laser light outputted from the 1st and the 2nd laser light sources 11 and 12 are collimated by the 1st and the 2nd collimator lenses 21 and 22 into two laser light beams, which reach a polarizing filter 24. The two laser beams are made parallel through the polarizing filter 24 and directed to a cylinder lens 25. The two laser beams passed through the cylinder lens 25 reach one of plural plane mirror surfaces 3E formed on flanks of the rotary polygon mirror 3.</p> |
