Compensation for marking-position errors along the pen-length direction, in inkjet printing

摘要

A calibration technique, for a printer having a plurality of different color ink printheads, which includes printing and scanning a test pattern. The test pattern is printed by each printhead printing a plurality of swaths having a length and distanced apart from each other. An optical sensor is used to scan the printed test pattern. Calibration is performed for each head by reading the swath length and the relative spacing of the swath and comparing the length to the spacing. This comparison is used to find the directional error for each head.