Abstract: A piezoelectric laminate comprises a piezoelectric layer and an insulating substrate layer rigidly bonded thereto. During poling, conditions are established under which a poling potential is established at the boundary of the layers which insures that a substantial part of the poling voltage is dropped across the piezoelectric layer. The poling voltage is maintained for a period greater than the time constant under the poling conditions of the material to which the poling voltage is applied. In one embodiment, the poling conditions are achieved by substantially enhancing the conductivity of the substrate layer relative to that of the piezoelectric layer. In a second embodiment, an intermediate bond layer is selectively switched from a non-conductive to a conductive state in response to a selected stimulus so as to form an electrode for facilitating the application of a poling field directly across the piezoelectric layer.

Abstract: A multiplexer circuit for effecting, in successive phases of operation, actuation of selected ones of respective groups of a plurality of capacitance actuated devices electrically represented by a plurality of series-connected capacitors, each device corresponding to an adjacent pair of the capacitors. The multiplexer includes a signal generator and a plurality of parallel electrical paths connected thereacrosss. Each path includes the common node formed by the capacitor pair corresponding to a respective one of the devices and first and second switches. A logic circuit is initially operable for respectively closing and opening the first and second switches of a selected path in one group and respectively opening and closing the first and second switches of the paths adjacent thereto for charging the two capacitors connected to the selected path.

Abstract: A pulsed droplet ink jet printer has at least one channel communicating with a nozzle. The side wall of the channel is formed as a shear mode piezo-electric actuator comprising an unpoled crystalline material. Electrodes applied to the actuator enable an electric field to be applied such that the actuator moves in transversely of the field to change the liquid pressure in the channel and thereby eject a droplet through the nozzle. The actuator can be made in two parts so as to deform, in cross section, to a chevron formation.