| 摘要 |
PURPOSE:To continuously vary the curvature of a cylindrical mirror or cylindrical lens in the length direction for the reduction of the curvature of a sagittal image plane so that the sagittal image plane curvature of a light beam is corrected as to the light beam scanning optical system equipped with an image formation optical system including the cylindrical mirror (cylindrical lens). CONSTITUTION:In the scanning optical system equipped with the image formation optical system including the cylindrical mirror (cylindrical lens) 7, a piezoelectric material 12 is stuck on the reverse surface of the cylindrical mirror (cylindrical lens) 7 having uniform curvature and a voltage applied to this piezoelectric material 12 is varied to continuously vary the curvature of the mirror (lens) 7 in the length direction so that the sagittal image plane curvature is corrected. |
