BI-DIRECTIONAL PRINTMODE FOR IMPROVED EDGE QUALITY

摘要

A method for incremental printing with an inkjet swath printer by ejecting drops of an ink from a printhead while scanning the printhead over a print medium, including determining a first edge and a second edge of each pixel in each row with respect to a first scanning direction. Moving the printhead in the first scanning direction while ejecting the drops of ink on the first edge of the pixels at a first firing frequency and on the second edge of the pixels at a second firing frequency and moving the printhead in a second direction opposite to the first scanning direction while ejecting the drops of ink on the second edge of the pixels at the first firing frequency and on the first edge of the pixels at the second firing frequency. Also a printing system for ejecting ink drops onto a medium, which includes a mechanism for scanning a carriage through a print zone over the medium, a printhead mounted on the carriage, the printhead having ink firing elements for ejecting an ink, and a controller for determining a first edge and a second edge of each pixel in each row with respect to a first scanning direction; the controller causing the carriage to scan the printhead in a first scanning direction while ejecting the drops of ink on the first edge of the pixels at a first firing frequency and on the second edge of the pixels at a second firing frequency; and the controller causing the carriage to scan the printhead in a second scanning direction opposite to the first scanning direction while ejecting the drops of ink on the second edge of the pixels at the first firing frequency and on the first edge of the pixels at the second firing frequency.