REDUCTION OF BANDING IN MULTI-PASS PRINTING MODE

摘要

PROBLEM TO BE SOLVED: To restrain low printing quality due to abnormality of a nozzle to a minimum level without drastically reducing the throughput of a printer. SOLUTION: A swath printer for improving the printing quality and a multi- pass printing method are provided. A printer 10 restrains the dot arrangement error on a printing medium 18 caused by adhesion of ink droplets from a low quality printing head nozzle 24 to a minimum level by providing a printing mask 62. The printing mask 62 has a mask pattern 87 capable of enabling a printing operation by driving the nozzle 24 most liable to generate the dot arrangement error by a relatively small number and driving the other nozzles 24 not liable to generate the dot arrangement error by a relatively large number. The printer 10 and method do not require use of a partial printing mode with corresponding reduction of the throughput.