| 摘要 |
PURPOSE: To flatly correct the nonuniformity if illuminance in the direction of a slit rectangle in continuos magnification over a wide range by displacing the degree of quantity corresponding to a variable magnification to that extension or reduction magnification so as to be cut in an optical path. CONSTITUTION: At the position of a fixed distance on the photosensitive body side of a lens 1, two illumination boards 8 fixed by one rod 10 turnable in the direction of the slit rectangle are fitted symmetrically to the direction of the slit rectangle. Then, at the time of magnification and non-magnification, a cam-shaped adjustment board 9 for changing the angle of the illumination boards 8 toward the rod 10 is rotationally displaced while being interlocked with the displacement of the lens for magnification so as to cut one part of light flux by inserting the illumination boards 8 according to that power. Namely, the illumination boards 8 are slid corresponding to the height of the adjustment board 9 through the move of the lens 1 due to the magnification. Thus, the non-uniformity of illuminance in the direction of the slit rectangle can be corrected flat in the continuous magnification over the wide range. |
