Future work

In this study, a transducer pulse with bipolar waveform was considered for driving a piezoelectric ink-jet printhead (Picojet). This succession of two square-wave pulses induces the suck-push-suck pulses of the pressure in the nozzle flow field. To modulate the drop size with a transducer pulse, it is worthwhile to further investigate the effect of the waveforms with more suck and push pulses on the drop formation of DOD ink jet printheads. The effect of other basic signal waveforms including sine and triangle shapes on the DOD drop formation could be incorporated into future research.

In addition, different printheads may have different relation between applied electric pulse and drop formation. Therefore, generality of the results shown in this study is a concern and further investigation using different systems is worthwhile.

This research is based on low-viscosity Newtonian flow. The results should be valid for many DOD applications whose viscosity of dispersed liquid is less than 20 cp. For non-Newtonian fluids such as colloidal and polymeric solutions, further investigation of the influence of a transducer pulse on the DOD drop formation is worthwhile.

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List of publications

1. J. M. Lai, C. Y. Huang, C. H. Chen, L. L. Kung and J. D. Lin, "Influence of liquid hydrophobicity and nozzle passage curvature on microfluidic dynamics in a drop ejection process," J. Micromech. Microeng. 20(1), p. 14 (2010).

2. J. M. Lai and J. D. Lin, "Numerical investigation of the effect of the transducer pulse on the drop ejection process," Proceedings of The 3rd IEEE International Conference on Nano/Molecular Medicine and Engineering, pp. 163-164 (2009), 18-21 October 2009, Tainan, Taiwan.

3. J. M. Lai and J. D. Lin, "An analysis of the effect of liquid hydrophobicity on the drop formation of a piezoelectric print head," Conference Proceedings of International Symposium on Microchemistry and Microsystems, pp. 88-89 (2010), 28-30 May 2010, Hong Kong.

4. J. M. Lai, K. Linliu and J. D. Lin, "Numerical investigation of the effect of a transducer pulse on the microfluidic control of a piezoelectric printhead," J.

Micro-Nanolithogr. MEMS MOEMS (Accepted).