| 摘要 |
<p>A three-pass printing method and related printing system are disclosed. In the first pass a pattern of 2 X 2 dot clusters are printed. The dot clusters are contiguous in the diagonal position and arranged in diagonal rows. After the first pass, the print medium (38) is advanced and a different group of nozzles are used to print a second pass over the same swath also using 2 X 2 dot clusters in a diagonal row in positions not printed during the first or second pass. A third pattern of 2 X 2 dot clusters is then printed in a third pass in the interstitial positions not printed during either the first or second passes. In this manner, all print positions are addressed by the print mode. The three-pass 2 X 2 dot clusters print mode avoids excessive amounts of data loss resulting from alignment errors between two successive print passes. The print mode also provides a print mask frequency that is not an integer divisor of the typical dither cell sizes. This provides the beneficial result that the print mode mask frequency does not beat with the dither cell frequency. The disclosed printing method ensures that different nozzles will be used for any pixel location in the dither cell. Thus if any single nozzle is defective, the other functioning nozzle will in part hide the defect. <IMAGE></p> |
