| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an optical scanner that can achieve a further reduction in size and acceleration without causing an increase in cost and a reduction in image quality.SOLUTION: An optical scanner includes an opening plate (opening member) having an opening on the light path between a light source and a rotary polygon mirror. In the opening, with respect to a first direction corresponding to the main scanning direction, the opening width in a second direction orthogonal to the first direction is gradually decreased from inflection parts (third positions) provided between the center part (first position) and end parts (second positions) toward the end parts, and the opening width a in the second direction at the center part, the opening width b in the second direction at the end parts, and the opening width c in the second direction at the inflection parts have the relationship of b<a≤c.</p> |
