ULTRASOUND TRANSDUCER DEVICE AND ULTRASOUND MEDICAL APPARATUS
There is provided an ultrasound transducer device including a plurality of piezoelectric single-crystal plates that are stacked such that polarization components thereof are alternately inverted. The plurality of piezoelectric single-crystal plates are stacked such that directions thereof in which strain deformation in a direction orthogonal to a direction of voltage application from electrodes respectively interposed between the plurality of piezoelectric single-crystal plates becomes largest coincide with each other. There is also provided an ultrasound medical apparatus including the ultrasound transducer device.
1 . An ultrasound transducer device comprising a plurality of piezoelectric single-crystal plates that are stacked such that polarization components thereof are alternately inverted, wherein
the plurality of piezoelectric single-crystal plates are stacked such that directions thereof in which strain deformation in a direction orthogonal to a direction of voltage application from electrodes respectively interposed between the plurality of piezoelectric single-crystal plates becomes largest coincide with each other.
2 . The ultrasound transducer device according to claim 1 , wherein the plurality of piezoelectric single-crystal plates are each made of a lead-free material.
3 . The ultrasound transducer device according to claim 2 , wherein the plurality of piezoelectric single-crystal plates are each made of a lithium niobate or lithium tantalate piezoelectric single crystal.
4 . The ultrasound transducer device according to claim 1 , wherein the plurality of piezoelectric single-crystal plates are each bilaterally symmetric with respect to a direction in which strain deformation in a direction orthogonal to a stacking direction becomes largest, as an axis of symmetry.
5 . The ultrasound transducer device according to claim 4 , wherein the plurality of piezoelectric single-crystal plates each include index portions on the axis of symmetry on front and rear surfaces thereof, respectively, the index portions enabling identification of the direction in which the strain deformation becomes largest and the front and rear surfaces.
6 . The ultrasound transducer device according to claim 5 , wherein the electrodes are respectively pattern-formed on the front and rear surfaces of the plurality of piezoelectric single-crystal plates, and parts of the electrodes are respectively formed as the index portions into such different shapes that enable identification of the direction in which the strain deformation becomes largest and the front and rear surfaces.
7 . An ultrasound medical apparatus comprising the ultrasound device according to any one of claim 1 to claim 6 .