A waveform design method for high DPI piezoelectric inkjet print-head based on numerical simulation

Abstract

In order to increase the Dots Per Inch (DPI) of the piezoelectric inkjet print-head, the width and length of the pressure chamber have become much smaller. This makes some previous waveform design methods no longer suitable for the design of high DPI piezoelectric inkjet print-head. In this paper, a new waveform design method based on numerical simulation for high DPI print-head is proposed. Different parameters of the unipolar trapezoidal waveform were optimized using the multi-physics simulation software COMSOL to acquire the optimal waveform for good quality jetting. And meniscus motion at the nozzle exit was measured to predict the jetting behavior of print-head and verify the simulation results. When the high DPI print-head was actuated by the optimized waveform with the rising time tr = 3 µs, dwelling time td = 16 µs, and falling time tf = 3 µs, the high DPI piezoelectric inkjet print-head was continuous injection.