| 摘要 |
PURPOSE:To compensate the parallel error between the reflecting surfaces and rotational axis of a rotary multiface mirror and reduce the cost of the scanner by arranging a reflector with 2 reflecting surfaces meeting at right angles in a fixed position on the light passage of light reflected by the rotary multiface mirror. CONSTITUTION:A rectangular reflector 7 with 2 reflecting surfaces 7a and 7b which meet at right angles is arranged on the light passage of a light reflected by a rotary multiface mirror 3 so that the edge line meets with a rotational axis 6 at right angles. After passing through a modulator 2, the beam from a laser 1 is reflected by the rotary multiface mirror 3, the reflecting surfaces 7a and 7b of the rectangular mirror 7 and again the rotary multiface mirror successively to scan a sensitive drum face 5 through an image formation lens 4. Since the parallel error generated between the reflecting surfaces and rotational axis of the rotary multiface mirror 3 is compensated as mentioned above, the cost of the scanner can be reduced. |
