| 摘要 |
PURPOSE: To correctly detect quantity of longitudinal and lateral misregistration without enlarging a size of a register mark. CONSTITUTION: In a misregistration quantity detecting method, two register marks printed by two print units are detected when a travelling web is to be printed in sequence by two or more of print units, and a quantity of misregistration generated during printing operation by the two print units based on the detected result is obtained by computation. Register marks 1C and 2C are simultaneously detected by first and second PSD (light position detecting element) sensors. A quantity of longitudinal misregistration is calculated from a difference in detecting timing, a distance between a sensor center and a register mark center is calculated based on a difference in output voltages at both ends, and a quantity of lateral misregistration is calculated from a difference in a distance to be obtained for each register mark. |
