| 摘要 |
PROBLEM TO BE SOLVED: To lighten the load on a polygon mirror driving motor, to suppress the power consumption and noise generation, and to shorter the actuation time extremely, and to prolong the life of a polygon mirror by preventing a mirror part from flawing and to prevent the deterioration of picture quality due to the sticking of dust to the mirror part. SOLUTION: The rotary polygon mirror 36 is formed of a light-transmissive synthetic resin and has a polygonal recessed part 48 formed at its center part. A reflecting film 51 having a high reflection factor is vapor-deposited on the side wall 48A of the recessed part 48 to constitute the mirror part. Consequently, the rotary polygon mirror reflects laser light made incident through the synthetic resin material by the reflecting surface of the mirror part formed on the side wall of the recessed part and emits it to the outside through the synthetic resin material. |
