| 摘要 |
PURPOSE:To simplify an operation for detecting deviation of printing position by setting a reference point on a medium, printing first marks by first printing means at equal intervals such that one of the marks coincides with the reference point, and printing second marks at second printing means at intervals different from the first marks. CONSTITUTION:A reference point O is set in the center of a length in a conveying direction of a medium and black marks are printed by a first printing means at equal intervals such that one of the marks coincides with the reference point O. Since a second printing means is positioned in the conveying direction of the medium downstream of the first printing means, red marks are printed, for example, at intervals of 9/10 of the black marks taking the conveying time into account and in positions adjacent to the black marks. As a result of the printing, when the red mark coincides with the black mark at the point O, there is no deviation in print timing between two printing means. When the red mark coincides with the black mark at other part than the point 0, there is print deviation. As the red mark is printed at the interval of 9/10 of the black mark, print deviation quantity can be detected accurately by coincidence point. |
