| 摘要 |
PROBLEM TO BE SOLVED: To make the potential of an exposure part uniform, to eliminate irregular printing or printing fogging caused by the dispersion of intermediate potential in a tri-level system and to obtain excellent printing by controlling so that the potential of the surface of a photoreceptor at a spot where the intensity of scanning light is high may be high and the potential of the surface of the photoreceptor at a spot where the intensity of the scanning light is low may be low. SOLUTION: The light is generated from a light source 1 such as a semiconductor laser and turned into parallel beams by a collimator lens 2. Thereafter, it passes a cylindrical lens 3, is deflected by a rotary polygon mirror 4 so as to perform scanning, passes an Fθlens 5 and is converged on the photoreceptor 6 electrified by an electrifier 8. The dispersed potential of the potential of the exposure part on the photoreceptor 6 caused by dispersion by the exposure of an optical scanner is stabilized by controlling potential distribution by a special electrifier 8. Therefore, the center part of the electrifier 8 is made close to the photoreceptor 6 and the peripheral part thereof is made far therefrom. Then, the potential of the surface of the photoreceptor at the spot where the intensity of the scanning light is high is made high and the potential of the surface of the photoreceptor at the spot where the intensity of the scanning light is low is made low. |
