IMAGE FORMING DEVICE, STREAK DETERMINATION METHOD AND STREAK DETERMINATION PROGRAM IN THE IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a printing device automatically making a determination of in particular a focus, streaks and the like and accurately determining whether or not printing quality is good, in regard to the printing device which self-diagnoses problems such as printing deviation, streaks and blurs.SOLUTION: A printing device includes a reading means for reading a focus determination test pattern printed by a printing head which is a target of a focus determination and a streak determination test pattern. The printing device analyzes the focus determination test pattern and the streak determination test pattern read by the reading means and automatically makes determinations of focus quality and streaks according to whether or not this analyzed result exceeds a predetermined threshold value.