| 摘要 |
PROBLEM TO BE SOLVED: To set the dimension of a positioning span in the subscanning direction of an incident mirror so as to effectively keep the accuracy of the rotating position of the incident mirror in the subscanning direction in accordance with the optical path length or the subscanning lateral magnification of an applied scanning optical system. SOLUTION: The optical scanner is equipped with the incident mirror M for folding an optical path between a light source 6 and a polygon mirror 8 for deflecting emitted light from the light source 6 between the light source 6 and the polygon mirror 8, and an expression of LO/(L1+L2)>0.06 mm is satisfied, wherein LO means the positioning span in the subscanning direction of the incident mirror M, L1 means optical path length from the reflection point of the incident mirror M to the polygon mirror 8 and L2 means optical path length from the polygon mirror 8 to the final surface of a scanning optical device. COPYRIGHT: (C)2004,JPO |
