Patent ID: 11944999
Assignee: TDK CORPORATION
Field: Chemical engineering (Chemistry)
Classification: CPC B  H | IPC B  H

Claim 1:
2. A bimorph type piezoelectric element which has a first main surface and a second main surface facing each other and of which the second main surface is bonded to a vibration member to form a vibration device, comprising:
a piezoelectric body in which a plurality of piezoelectric layers are laminated and form a first active region and a second active region, the first active region disposed on the first main surface side between the first and second main surfaces, and the second active region disposed closer to the second main surface side than the first active region between the first and second main surfaces and displaced in opposite directions to the first active region;
a first internal electrode that applies an electric field to the first active region and is disposed inside the piezoelectric body; and
a second internal electrode that applies an electric field to the second active region and is disposed inside the piezoelectric body,
wherein each of the first active region and the second active region includes at least one of the piezoelectric layers, and
when a displacement amount of the first active region is X1 and a displacement amount of the second active region is X2, X1<X2 is satisfied.