Printer and feeding control method

摘要

An ink jet head is fed in a main-scan direction to record one line on a recording paper. Thereafter, the recording paper is fed in a sub-scan direction for one line. A corrected feeding amount A is calculated by adding a correction value C1 to a basic feeding amount B. The correction value C1 is determined by a formula, C1=2.D.(R-½), wherein p represents an interval between dots recorded on recording paper in the sub-scan direction, and k represents a range of unevenness in the feeding amount caused by structural factors of sub-scan feeding means. For example, D=(p-k)/2. R is a random number in a range between 0 and 1. Gradation unevenness and/or black and white streaks caused by periodical feeding unevenness become inconspicuous since the correction value C1 is changed on a random basis.