| 摘要 |
PURPOSE:To make it possible to easily correct spot positions of plural beams split to line up in approximately parallel with each other by arranging deflecting means for deflecting optical paths independently on optical paths of the beams split to a plural number by luminous flux splitting means. CONSTITUTION:For example, a laser plotter has beam array correcting devices 72, 73 for correcting the spot positions on the image planes of the plural beams emitted from beam separators 21, 22. These beam array correcting devices 72, 73 have the wedge optical elements (deflecting means) 81 for deflecting the optical paths and supporting members 80 for rotation adjustably supporting these wedge optical elements 81. The pitches of 8 pieces each of the beams L5a to L5h and L6a to L6h split to line up in approximately parallel with each other within approximately the same plane by the beam separators 21, 22 in the sub-scanning direction are properly changed by using such beam array correcting devices 72, 73, by which the respective spots are so adjusted as to line up respectively at the adequate pitches. |
