<title>Process control for improvement of print quality and lifetime of bubble-jet printers</title>

Abstract

This paper is concerned with experimental studies on process control for driving the heating elements of bubble-jet printheads. Process control plays a key role for print quality as well as for life time of bubble-jet printers. An experimental set-up was built which allows the automatic registration of a series of video images. With this set-up it is possible to study the influence of the driving signal on the drop formation from bubble nucleation to printing. The pulse width of a square reference signal has been split into a burst consisting of multiple pulses with smaller pulse widths. The delay and the number of the individual pulses have been varied. An optimal drive signal has been determined and applied to a commercial printhead. As a consequence of this optimization, a reduction of the input energy and an increase of the droplet speed of approximately 30 percent compared to the single square pulse have been achieved while the mass of the droplet remained unchanged. As a result, burst pulses with optimally modulated pulse width contribute to a substantial increase of the life time of printheads. Additionally, in case of satellite droplets their size has been reduced and merging with the main droplet occurs faster which improves the print quality.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.