Patent ID: 7393069

Claim:
An image forming apparatus, comprising: a liquid droplets ejection head which has a plurality of nozzles in a main scanning direction, the liquid droplets ejection head ejecting droplets of liquid toward a predetermined recording medium from one of the nozzles selected from the plurality of nozzles according to a predetermined image signal so that an image comprising a plurality of dots corresponding to the image signal is formed on the recording medium; a relative movement device which moves the liquid droplets ejection head and the recording medium relative to each other in a sub-scanning direction by causing the liquid droplets ejection head to scan the recording medium several times in order to eject the droplets of the liquid so that the adjacent dots in the sub-scanning direction are formed by overlapping with each other, wherein M is an integer more than an overlap degree of the adjacent dots in the sub-scanning direction, and then N is a natural number; a fixing time specifying device which specifies a fixing time during which each of the dots is fixed on the recording medium; a deposition order setting device which sets a deposition order of the dots in the sub-scanning direction according to the overlap degree of the adjacent dots in at least the sub-scanning direction wherein the deposition order setting device divides a row of the dots in the sub-scanning direction into N groups with the M as a basic unit, and the deposition order setting device sets the deposition order of the dots in the sub-scanning direction so that the dots are deposited with (M−1) dots interval; and a deposition time difference setting device which sets a difference between deposition times of the adjacent dots in the sub-scanning direction so that the difference between the deposition times of the adjacent dots in the sub-scanning direction is more than the fixing time of each of the dots.