PROBLEM TO BE SOLVED: To provide an ultrasonic device comprising a backing portion for suppressing unnecessary ultrasonic waves and being capable of achieving a reduction in thickness, and an ultrasonic probe comprising the ultrasonic device, an electronic apparatus comprising the ultrasonic probe, and an ultrasonic imaging device.SOLUTION: An ultrasonic device which is an ultrasonic device 1 for performing transmission/reception of ultrasonic waves, comprises: ultrasonic elements 10 including first surfaces and second surfaces each emitting the ultrasonic waves； and a backing portion 20 for supporting the second surfaces of the ultrasonic elements 10 and being capable of attenuating the ultrasonic waves emitted to second surface sides. The backing portion 20 comprises micro lenses 200 disposed at positions corresponding to the ultrasonic elements 10 at the second surface sides of the ultrasonic elements 10, and a backing member 210 having slit holes 211 through which the ultrasonic waves transmitted through the micro lenses 200 pass. Further, the ultrasonic elements 10 are disposed in an array, and the micro lenses 200 are disposed in the array so as to correspond to the ultrasonic elements 10.SELECTED DRAWING: Figure 7【課題】不要な超音波を抑制し、薄型化を図ることができるバッキング部を備えた超音波デバイス、超音波デバイスを備えた超音波プローブ、超音波プローブを備えた電子機器、および超音波画像装置を提供する。【解決手段】超音波デバイスは、超音波の送受信を行う超音波デバイス１であって、超音波を射出する第１面および第２面を含む超音波素子１０と、超音波素子１０の第２面を支持し、第２面側に射出される超音波を減衰可能なバッキング部２０と、を備え、バッキング部２０は、超音波素子１０の第２面側で、超音波素子１０に対応した位置に配置されたマイクロレンズ２００と、マイクロレンズ２００を透過した超音波を通過させるスリット孔２１１を有するバッキング部材２１０と、を備えている。また、超音波素子１０はアレイ状に配置され、マイクロレンズ２００は超音波素子１０に対応してアレイ状に配置されている。【選択図】図７
