| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical scanner and an image forming apparatus capable of forming a high quality image. SOLUTION: In a rotary polygon mirror 50 of the optical scanner 18, a flatness difference between adjoining reflecting surfaces is limited to 1.5λor less. Therefore, a slippage amount of an exposure position is suppressed in the part of adjoining scanning areas, and image quality is improved. Especially, in a multi-exposing system for overlapping the scanning areas and exposing the same position multiple times, an image density is decreased against a predetermined density due to the misalignment of the exposure position. However, since the flatness difference between the adjoining reflecting planes of the rotary polygon mirror is limited to 1.5λor less, the misalignment of the exposure position is suppressed in the main scanning direction, and banding and white stripe generation due to density decrease can be prevented. That is, high quality image forming can be performed. COPYRIGHT: (C)2005,JPO&NCIPI |
