| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a piezoelectric actuator and a manufacturing method of the piezoelectric actuator which minimizes electrostatic capacitance in the piezoelectric actuator.SOLUTION: A superimposition part 44a of a lower electrode 44 which is arranged between an ink separation layer 41 and a piezoelectric layer 42 and is retained at a ground potential is superimposed on both end parts in the transportation direction of a pressure chamber 10. A superimposition part 45a of an intermediate electrode 45 which is arranged between a piezoelectric layer 42 and a piezoelectric layer 43 and is retained at a driving potential is superimposed on a center part in the transportation direction of the pressure chamber 10. An upper electrode 46 arranged on the upper surface of the piezoelectric layer 43 is superimposed on almost the whole region of the pressure chamber 10. A first active part 61 held by the superimposition part 45a of the piezoelectric layer 43 and the upper electrode 46 is depolarized upward, and a second active part 62 held by the superimposition part 44a of the piezoelectric layers 42, 43 and the upper electrode 46 is depolarized downward. A part 63 in which an electric field of a predetermined intensity or more is generated in accordance with a voltage between the lower electrode 44 and an intermediate electrode 45 has a polarization smaller than the polarization in the second active part 62.</p> |
