IMAGE FORMING APPARATUS AND METHOD FOR ADJUSTING DEVIATION OF STRIKING POSITION

PROBLEM TO BE SOLVED: To improve quality in formation of an image formed by ejecting droplets in both of a going path and a returning path in a main scanning direction much further by correcting deviation of a striking position of an ink droplet, and to lower an incidence rate of rubbing of a target by a discharge head. SOLUTION: The same pattern is printed by the going path and the returning path of a printing head 24. When the striking position of the ink droplet is on this side of an ideal striking position, a platen gap PG is made large, and when the striking position of the ink droplet is on the inner side than the ideal striking position, the platen gap PG is made small. The platen gap PG is changed within an upper limit value PGmax set in accordance with discharging ability (flying speed of the ink droplet) of the printing head 24. Thus, the deviation of the striking position of the ink droplet different every machine body is corrected without adjusting discharge timing of the printing head 24, and the platen gap PG is made large for the printing head 24 having high discharging ability (high flying speed of the ink droplet), whereby a risk of paper rubbing is kept low without deteriorating image quality. COPYRIGHT: (C)2010,JPO&INPIT