| 摘要 |
<p>PROBLEM TO BE SOLVED: To restrain a variation in the concentration by a difference in a fixation mode of ink, by restraining the extension of time required for image formation output, in an image formation device for discharging an ink drop to a sheet by a multipass system.SOLUTION: When a difference of a main scanning directional position for turning back a carriage exceeds a predetermined threshold value in reciprocating motion equivalent to two times of continuing in the sub-scanning direction, and when there is an image area of continuing in the sub-scanning direction in the reciprocating motion equivalent to two times, a quantity of changing the main scanning directional position for turning back the carriage is limited to a predetermined upper limit value in the reciprocating motion of one time, and the main scanning directional position for turning back the carriage is gradually changed with every reciprocating motion of one time, to thereby control so as not to exceed a predetermined period on a difference in a period up to the discharge timing of ink in a return passage from the discharge timing of the ink in a forward passage.</p> |
