PURPOSE: To make corrections as to rotational deviation and parallel movement in scanning on an origitnal, by detecting a deviation value from a fixed position on the original by making use of a reference line.
CONSTITUTION: By making an auxiliary scan in a direction perpendicular to reference line 4S, the number na of picture elements between points A0 and A where an "a"-th scanning line crosses reference line 4S and straight line 4 on the original is obtained. In the same way, the number nb of picture elements between intersections B0 and B is also obtained as to a "a+N"-th scanning line. Consequently, turning angle of the original can be found by expression tan =(na-nb)/n0. Then, the original with its rotational deviation corrected is placed in parallel to reference lines 3S and 4S. Therefore, X-directional deviation nx can be obtained by detecting straight line 4, and y-directional deviation ny by detecting straight line 3. The parallel movement of the original is corrected according to this.
KATAOKA HIROSHI
SUZUKI ISAO
YOKOTA SHIYOUZOU
