Patent ID: 8113635

Claim:
A liquid discharge apparatus, comprising: a cavity unit including a nozzle for discharging liquid and a pressure chamber which communicates with the nozzle and has an opening; and a piezoelectric actuator which includes a first ceramic layer covering the opening of the pressure chamber, second and third ceramic layers sequentially stacked on the side opposite to the side on which the first ceramic layer covers the opening, a first electrode disposed between the first ceramic layer and the second ceramic layer, a second electrode disposed between the second ceramic layer and the third ceramic layer and a third electrode sandwiching the third ceramic layer with the second electrode, and said piezoelectric actuator being fixed to the cavity unit, wherein the piezoelectric actuator is displaced by applying voltage between the first electrode and the second electrode and between the second electrode and the third electrode, thereby applying discharge pressure to liquid filled in the pressure chamber, the first electrode and the third electrode are connected to at least two terminals which are provided on the piezoelectric actuator, and independent of each other on the piezoelectric actuator electrically, respectively.