Patent ID: 8678566

Claim:
A piezoelectric element comprising: a first electrode including: a first electroconductive layer having a first surface; and a second electroconductive layer mainly containing lanthanum nickelate disposed on the first surface, the second electroconductive layer having a second surface at the first surface side; a second electrode; and a piezoelectric layer disposed between the first electrode and the second electrode with the second electroconductive layer closer to the piezoelectric layer than the first electroconductive layer, the piezoelectric layer having first sides in a first direction and second sides in a second direction, wherein the first electrode, the piezoelectric layer and the second electrode overlap with each other when viewed in a direction normal to the first surface to form an overlap portion acting as a driving portion, and wherein at least part of the second electroconductive layer is disposed within the sides of the first surface within the driving portion wherein boundaries of the driving portion are determined by an end of the second electrode in the second direction and an end of the first electroconductive layer in the second direction, wherein the second electrode is disposed on a portion of the first sides of the piezoelectric layer and on one of the second sides of the piezoelectric layer in the second direction that intersects the first direction, and the second surface has a smaller area than the first surface within the driving portion.