| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain an optical scanner carrying out both stabilization of a light collection position and correction of surface error on a surface to be scanned by using an over filled optical system. <P>SOLUTION: The optical scanner includes: a light source 11; a deflector 14 having a plurality of plane reflection surfaces; a collimator lens 12 and a free-curved surface lens 13 arranged in an optical path between the light source 11 and the deflector 14, scanner lenses 1, 2 arranged in an optical path between the deflector 14 and a photoreceptor 10 and composed to have reflection surfaces of the deflector 14 and the photoreceptor 10 in respective deflection angles in an image range to double for a sub scanning direction. The width of the beam flux going toward the deflector 14 from the lens 13 is wider than the reflection surface of the deflector 14 regarding the scanning direction of the deflector 14. An average curvature in the range of the beam flux on a wave front of the beam flux going toward the deflector 14 is smaller in the deflection angle equivalent to an end section of scanning width regarding the sub scanning direction "z" in a beam flux passing range of the lens 13 in the deflection angle equivalent to the end section in the scanning width and in a beam flux passing range of the lens 13 in the deflection angle equivalent to the center of the scanning width. <P>COPYRIGHT: (C)2012,JPO&INPIT |
