SKEWED INK JET ARRAY
Original Publication Date: 1980-Oct-31
Included in the Prior Art Database: 2004-Apr-02
Xerox Disclosure Journal
In the ink jet printing art, it is known that droplets are directed onto specific picture elements of a receiving surface by charging them individually and using electrostatic fields to deflect them. Figure 1 represents a typical system in which nozzle 1 forms the droplets which are charged by passage through charging tunnel 2 and deflected by the electric fields applied between deflecting plates 3. Undeflected droplets are caught by gutter 4 and deflected droplets fall within the range 5 on the receiving surface 6. With this arrangement, providing the high accuracy required for drop placement is extremely difficult because of the influence of air motion and the change of path length with deflection angle. Moving air currents caused by the moving droplets decrease in velocity with increasing distance from the droplet stream. Hence, droplets experiencing greater deflection tend to move more slowly than those experiencing lesser deflection. This reduction in velocity combined with the longer path length produces a positioning error which increases with droplet deflection.