Abstract: The present invention relates to liquid projection apparatus in the form of a face-shooter array. Material layers are used as the basis to fabricate the device to overcome constructional difficulties associated with other technologies. The device utilizes excitation of the surface layers (100) incorporating nozzles (8) which are arranged over one surface layer with addressability, forming a liquid projection array, capable of operation at high frequencies with a wide range of liquids.

Abstract: An ink-jet head is formed by partitioning a plurality of ink chambers made from piezoelectric members from each other. Ink chambers which emit ink and dummy ink chambers which do not emit ink are arranged alternately, and ink is supplied to the ink chambers from a common ink chamber. This ink head is used to sequentially perform emission of an ink drop from the ink chambers for a plurality of times, to achieve gradation printing, while the emission speed of the ink drops is gradually increased such that ink drops emitted later are merged with ink drops emitted earlier thereby to form a one-dot liquid drop. In this case, where adjacent ink chambers with a dummy ink chamber inserted therebetween are simultaneously driven, timings of drive pulse voltages q1 and q2 applied to both of the adjacent ink chambers are shifted from each other such that the pressure in one of the adjacent ink chambers is decreased when the pressure in the other of the adjacent ink chamber is increased.

Abstract: The selected ink channels of a drop-on-demand ink jet printer are caused to expand and then contract, ejecting ink droplets by the application of unipolar voltages first to selected channels and then to non-selected channels. Further unipolar voltages, delayed in time by 2L/c and scaled by a pressure wave reflection coefficient r of the nozzle, effect prompt cancellation of residual pressure waves so that adjacent channels are ready for actuation with minimum delay.

Abstract: In a multi-drop system, a drive pulse voltage for increasing a volume of an ink chamber is applied for a time of AL, a drive pulse voltage for decreasing the volume of the ink chamber is subsequently applied for a time of 2AL, application of the drive pulse voltage is thereafter paused for a time of AL, and the same timing operation is thereafter repeated again to perform emission of an ink drop a plurality of times, where AL is a time required for a pressure wave in an ink chamber to be transmitted from an end to the other end in the ink emission direction. The drive pulse voltage for emitting a last ink drop forming a part of a one-dot liquid drop is applied for a time of 2AL, application of the drive pulse voltage is thereafter paused for a time of AL, and a dumping pulse voltage is thereafter applied in a direction in which the volume of the ink chamber is decreased.

Abstract: An inkjet printhead comprises an array of parallel channels separated one from the next by side walls transversely displaceable in response to an actuating signal. Pattern dependent crosstalk is avoided by applying to a channel selected for actuation a signal held at a given non-zero level for a period of length greater than that the length of the period at which the velocity of droplets ejected from said channel is at its maximum and at which the velocity of a droplet ejected from said selected channel is substantially independent of whether or not channels in the vicinity of said selected channel are similarly actuated to effect droplet ejection simultaneously with droplet ejection from the selected channel.