| 摘要 |
PURPOSE:To eliminate the non-parallel state of forward and backward scanning lines and to correct and avert disturbance in an auxiliary scanning direction by providing a means for deflecting the auxiliary scanning directions which parallels the forward and backward scanning lines with each other and an optical means for correcting the disturbance of the scanning lines by wobbling. CONSTITUTION:The optical scanner is constituted of an AOD7 which deflects the laser beam 5 from a light source 6 to the auxiliary scanning direction, a galvanometer mirror 8 on which the beam 5 emitted from the AOD7 is made incident, cylindrical lenses 9, 10 disposed before and behind the mirror 8 and a condenser lens 12 which condenses the beam 5 past the lens 10 onto a scanning plane 1. The AOD7 corresponds to the means for deflecting the auxiliary scanning direction and the lens 9, 10 correspond to the optical means for correction. The AOD7 receives the control signal from a control circuit 13 and determines the non-parallel state of the forward and backward scanning lines by calculation from the number of forward and backward oscillations, the moving speed of the scanning plane, etc. while synchronizing the beam 5 emitted from the AOD7 with the forward and backward oscillations of the mirror 8. The forward and backward scanning lines to be formed on the plane 1 are deflected in the auxiliary scanning direction according to the degree of the non-parallel state and are thereby paralleled.
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