| 摘要 |
PROBLEM TO BE SOLVED: To reduce positional changes of a scanning lens, to prevent image quality degradation.SOLUTION: A scanning lens 12 includes a first plane 12-1 provided on the side of an exit surface at one end in a scanning direction, and a second plane 12-2 provided on the side of the exit surface at the other end in the scanning direction of the scanning lens 12. A housing 14 includes a first support part 15-1 having a reference plane 15-5, and a second support part 15-2 having a reference plane 15-6. In the scanning lens 12, a position in an optical axis direction of the scanning lens 12 is decided with respect to the housing 14 when the first plane 12-1 comes in contact with the reference plane 15-5 and the second plane 12-2 comes in contact with the reference plane 15-6. |
