| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact optical scanner without reducing image quality.SOLUTION: In orthogonal projection on a plane orthogonal to a rotation axis of an optical deflector, a width of a light flux incident on the optical deflector is smaller than a width of one deflection reflection plane of the optical deflector. A part of the incident light flux is vignetted by the optical deflector when the light flux deflected by the optical deflector travels toward a synchronization detection sensor, travels toward a write start position, and travels toward a write end position. When there is a burr projecting from a plane 1 toward a plane 4 in a boundary between the plane 1 and the plane 4, a rotary polygon mirror rotates so that the light flux from the light source is made incident on the plane 4 to the plane 1. |
