Laminated piezoelectric body, laminated piezoelectric body manufacturing method, and ultrasound transducer and ultrasound diagnostic device using laminated piezoelectric body

摘要

In a laminated piezoelectric body, a laminated piezoelectric body manufacturing method, an ultrasound transducer, and an ultrasound diagnostic device according to the present invention, a plurality of mutually laminated piezoelectric bodies are electrically connected in parallel to each other, and each of the plurality of piezoelectric bodies arranges an orientation of residual polarization or a crystal axis that is related to an electrical displacement or a sign of an electric field due to a direct piezoelectric effect in a direction which reduces sensitivity in a first resonance mode and increases sensitivity in a second resonance mode of a higher order than the first resonance mode with respect to an axis of a first-level piezoelectric body on a fixed end-side.

主权项

1. An ultrasound transducer comprising:
only three mutually laminated piezoelectric layers of equal thickness; a plurality of electrodes arranged at interlayers of the mutually laminated piezoelectric layers and on surfaces of piezoelectric layers at both ends; and two connecting wirings which mutually connect the respective piezoelectric layers in parallel by coupling farther-side electrodes of mutually adjacent piezoelectric layers, wherein a first-level piezoelectric layer of the laminated piezoelectric layers includes a fixed end-side and an opposite side on which the others of the piezoelectric layers are laminated, the respective piezoelectric layers are arranged such that an orientation of the residual polarization or the crystal axis of the first-level piezoelectric layer is in a first direction, an orientation of the residual polarization or the crystal axis is in the first direction for a second-level piezoelectric layer that is in contact with the first-level piezoelectric layer and in a second direction, which is an opposite direction to the first direction, for a third-level piezoelectric layer that in contact with the second-level piezoelectric layer, and the mutually laminated piezoelectric layers transmit an ultrasound wave into a subject and receive an ultrasound wave from the subject.