Tonejet Limited

Peter James Brown

Andrew John Clippingdale

John Lawton Sharp

Robin Timothy Bacon

Ammar Lecheheb

Ewan Hendrik Conradie

The invention relates to a method of printing a two-dimensional bit-mapped image having a number of pixels per row, the printhead having a row of ejection channels and each ejection channel having associated ejection electrodes to which voltages are applied in use. During printing, in order to cause volumes of fluid to be ejected from selected ejection channels of the printhead for printing, voltage pulses having values of predetermined amplitude and duration as determined by respective image pixel bit values generated by a raster image processor are applied, at a given pulse period, to the electrodes of the selected ejection channels. The part of the raster image corresponding to an ejection channel is scanned to determine the number of adjacent non-printing pixel periods prior to a pixel to be printed and, immediately prior to the printing of said pixel, a voltage pulse, having a value predetermined in accordance with the time, measured in units of the given pixel period, between the last pixel to be printed and said pixel to be printed, is applied to the ejection electrode.

Printhead calibration and printing

A drop on demand printer is provided having: an ink ejection location for ejecting ink droplets, the ejection location having an associated ejection electrode for causing electrostatic ejection of the droplets from the ejection location; an intermediate electrode spaced from the ejection location, and in use disposed between the ejection location and a substrate onto which the droplets are printed in use; wherein either the ejection electrode or the intermediate electrode is coated with a film, the film being formed from a blend of a polymer insulating host and a conducting polymer dopant.

Growing community of inventors

Royston, United Kingdom

Peter James Brown