PROBLEM TO BE SOLVED: To provide a small ultrasonic vibrator which has a stable vibration element characteristic without needing a large-scale incidental facility and has a suppressed cost, and to provide an ultrasonic medical apparatus using the ultrasonic vibrator.SOLUTION: A ultrasonic vibration device 2 is configured so that: a plurality of piezoelectric monocrystal layers 44a to 44d are alternately laminated with top and back plate surfaces by making each crystal orientation as the same direction； wiring from a power source is alternately connected with a plurality of electrode layers 45a to 45e in order of lamination； a laminate vibrator 41 is vibrated by making a direction of shearing distortion, produced in the adjacent piezoelectric monocrystal layers 44a to 44d by voltage application to a plurality of electrode layers 45a to 45e, alternate； and a waveform rectification part 42 rectifies vibration in a direction vertical to a lamination direction of the plurality of piezoelectric monocrystal layers 44a to 44d and excites the vibration. The ultrasonic medical apparatus 1 is provided with the ultrasonic vibration device 2.【課題】 大掛かりな付帯設備を必要としなくとも安定した振動素子特性を備えて、且つコストを抑えた小型な超音波振動子と、この超音波振動子を用いた超音波医療装置の提供。【解決手段】 複数の圧電単結晶層４４ａ～４４ｄが結晶方位を同一方向として表裏の板面が交互に積層され、複数の電極層４５ａ～４５ｅが積層順に電源からの配線が交互に接続され、複数の電極層４５ａ～４５ｅへの電圧印加により隣接する圧電単結晶層４４ａ～４４ｄに生じるせん断歪の方向を互い違いとして積層振動子４１を振動させて、波形整流部４２が複数の圧電単結晶層４４ａ～４４ｄの積層方向に対して垂直に振動を整流して励振する超音波振動デバイス２と、この超音波振動デバイス２を備える超音波医療装置１。【選択図】図３
