Scaling of Piezoelectric Drop-on-Demand Jets for High Resolution Applications

As drop-on-demand ink jet systems strive for higher image quality, it is desirable to print with increased resolution. Higher resolution necessitates scaling jet designs to decrease drop volumes, while maintaining the high drop velocities needed for accurate drop placement. Using computer modeling in combination with experimental builds in machined carbon printheads, many variations of ink jet can be designed and tested in a short time. Finite element, lumped parameter, and three dimensional fluid modeling software are used to study mechanical properties, frequency response, and drop formation of Spectra’s drop-on-demand ink jets. These tools allow the designer to develop a test matrix which is sensitive to the important parameters. In-house machining of printhead parts facilitates the building and testing of many jet designs in a single printhead. Using these tools in combination, the redesign of piezo jets for reduced drop volume was successfully demonstrated.