| 摘要 |
PURPOSE:To reduce the angle of oblique incidence of an incidence optical axis and prevent scanning line curving by simple constitution by making write luminous flux at a slight tilt angle incident on the plane of deflection of deflected luminous flux. CONSTITUTION:Light from a semiconductor laser 1 travels straight in the transparent part of the lower half part 7a of a mirror 7, reflected light 4' from a rotary polygon mirror 4 is deflected on a plane where its optical axis crosses a plane containing the optical axis of incident light at a slight angle, and the deflection range is an angle range nearly equal to both sides of the optical axis of the incident light. The reflected luminous flux is reflected by the reflecting surface of the upper half part 7b of the mirror 7 at about 90 deg. to the plane of deflection and made incident on a photosensitive body drum 6 through a cylindrical lens 5. In this case, the write luminous flux incident on a deflector 4 is made incident at the slight tilt angle on the plane of polarization of the deflected luminous flux reflected by the deflector 4 and then the deflected luminous flux can be made incident on the drum 6 without interfering with optical elements 1, 2, and 3 on the optical path of incidence, thereby scanning the drum 6 while scanning line curving is reduced greatly. |
