| 摘要 |
PROBLEM TO BE SOLVED: To express middle tone without lowering image quality. SOLUTION: In a head driver of the control part of an ink jet printer, pulse voltages having waveforms 1a-1e are applied in order to drive piezoelectric elements and ink dots having a plurality of diameters are printed to express middle tone. The waveforms 1a-1e of these pulse voltages are set so that voltages are gently raised as pulse amplitude becomes large and the sudden strain of piezoelectric elements is prevented and ink drops especially large in diameter fly stably to prevent satelite dots, dot split noise and impact position shift generated heretofore. |
