| 摘要 |
PROBLEM TO BE SOLVED: To detect ejection failure certainly at a high speed without the risk of influencing a printing operation sequence, and detect ink adhesion on a head surface provided with an ejection opening in an ink-jet head comprising a plurality of ejection openings for ejecting an ink arranged, for executing a printing operation by moving the same relatively in a scanning direction with respect to a printing medium. SOLUTION: In a process of moving an ink-jet head 113 relatively in a scanning direction, a light beam 111a is directed in the direction across the locus of the ejected ink, obliquely with respect to the arrangement direction of a plurality of ejection openings as well as an ink is ejected from the plurality of the ejection openings according to predetermined data for detecting the ink ejection state from the plurality of the ejection openings based on the state of blocking the light beam by the ejected ink. Moreover, ink adhesion on a head surface is judged by the detection contents. |
