| 摘要 |
PROBLEM TO BE SOLVED: To actualize a new 'scanning line pitch adjusting method' for easily and accurately adjusting the scanning line pitch of multi-beam scanning and a 'light source unit for multi-beam scanning' for actualizing the method. SOLUTION: By the method of adjusting the intervals of scanning lines on a scanned surface in the multi-beam scanning, respective light beams while converged in the vertical scanning direction individually by individual cylindrical lenses 5A and 5B are guided to a beam multiplexing means 6, and the light beam group multiplexed by the beam multiplexing means 6 is guided to the deflecting and reflecting surface position of an optical deflector 12 and imaged nearby the deflecting and reflecting surface as linear images which are long in the horizontal scanning direction by the light beams. Mirrors 4A and 4B are arranged on optical paths of >=1 light beam, the travel directions of the light beams are deflected and adjusted to the vertical scanning direction by swinging and adjusting the reflecting surfaces of the mirrors, and >=1 of the cylindrical lenses 5A and 5B is adjusted by translational displacement in the vertical scanning direction to adjust the intervals of the scanning lines on the scanned surface. |
