用于磁声耦合刺激的64阵元相控阵超声换能器的设计

Design of 64 element phased array ultrasonic transducer for transcranial magneto-acoustic stimulation

本研究基于磁声耦合刺激技术(transcranial magneto-acoustic stimulation,TMAS)的需求,设计了用于线性64阵元相控阵的超声换能器,探究相控阵超声换能器压电晶体宽度及间距,优化超声换能器聚焦声场分布。采用MATLAB软件建立相控阵换能器模型,仿真聚焦声场分布。搭建三维声场分布测试的实验平台,对定制换能器进行声场分布测试并与仿真结果进行一致性分析,验证换能器性能。仿真得到换能器参数为阵元宽度4.5 mm,阵元间距1 mm,定制的64阵元相控阵换能器在XZ方向上声场焦斑的测量值为(3.4 mm),与仿真值(3.1 mm)基本一致。结果表明,本研究设计的换能器声场特性可以满足TMAS刺激的需求,为磁声耦合刺激技术应用提供了技术基础。

Based on the needs of transcranial magneto-acoustic stimulation(TMAS)technology,a linear 64 element phased array ultrasonic transducer for TMAS was designed,the width and spacing of piezoelectric crystals of phased array ultrasonic transducer were explored,and the focused acoustic field distribution of ultrasonic transducer was optimized.The phased array transducer model was established by MATLAB software to simulate the focusing acoustic field distribution.We built an experimental platform for three-dimensional acoustic field distribution test,tested the acoustic field distribution of the customized transducer,and analyzed the consistency with the simulation results to verify the performance of the transducer.The simulation results showed that the transducer parameters were array element width of 4.5 mm and array element spacing of 1 mm.The measured value of acoustic field focal spot of customized 64 array phased array transducer in XZ direction was 3.4 mm,which was basically consistent with the simulation value(3.1 mm).The results show that the acoustic field characteristics of this transducer can meet the needs of TMAS stimulation,and provides a technical basis for the application of magneto-acoustic stimulation technology.