Print direction dependent firing frequency for improved edge quality

摘要

A printing system for ejecting rows and columns of 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 ejection elements arranged in first and second columns of ink ejection elements arranged perpendicular to a scanning direction and a controller for causing the carriage to scan the printhead in a first scanning direction while controlling the ejection of drops of ink from the first column of ink ejection elements at a first ejection frequency and the ejection of drops of ink from the second column of ink ejection elements at a second ejection frequency and causing the carriage to scan the printhead in a second scanning direction opposite to the first scanning direction while controlling the ejection of drops of ink from the first column of ink ejection elements at the second ejection frequency and the ejection of drops of ink from the second column of ink ejection elements at the first ejection frequency.A method of printing by ejecting drops of ink onto a media from a printhead having ink ejection elements arranged in first and second columns of ink ejection elements arranged perpendicular to a scanning axis by moving the printhead in a first scanning direction above the media while ejecting the drops of ink from the first column of ink ejection elements at a first ejection frequency and ejecting the drops of ink from the second column of ink ejection elements at a second ejection frequency and then moving the printhead in a second scanning direction above the media opposite to the first scanning direction while ejecting the drops of ink from the first column of ink ejection elements at the second ejection frequency and ejecting the drops of ink from the second column of ink ejection elements at the first ejection frequency.