治疗超声系统中换能器声学性能的声全息法评估  

Acoustic holography evaluation of transducer performance in therapeutic ultrasound system

作　　者：李珊珊 白景峰[1,2] 吉翔 LI Shanshan;BAI Jingfeng;JI Xiang(Biomedical Instrument Institute,School of Biomedical Engineering,Shanghai Jiao Tong University,Shanghai 200030,China;Shanghai Med-X Engineering Research Center,Shanghai Jiao Tong University,Shanghai 200030,China)

机构地区：[1]上海交通大学生物医学工程学院生物医学仪器研究所,上海200030 [2]上海Med-X工程技术中心,上海200030

出　　处：《声学技术》2024年第1期43-54,共12页Technical Acoustics

摘　　要：换能器的聚焦特性等声学性能是治疗超声系统的重要参数之一,在出厂前和日常维护中须精确测量。目前常用的水听器测量法结果准确,但受声压幅度及测量效率的限制,高功率量程的声功率计造价较高;而基于声全息的表面振动模式测量法可作为高声压下水听器和声功率计测量法的补充,测量小声压平面并对高幅度声压焦域进行重建。为评估声全息法的准确性,文章研究了在小声压下使用基于声全息的表面振动模式测量法对声场进行测量和重建,分析该方法与水听器测量结果之间的功率和声压误差,以及影响误差的重要参数。结果表明,基于声全息的表面振动模式测量法可重建得到与水听器直接测量相近的结果,有望对高声压下工作的换能器的声场特性进行评估。The acoustic performance of transducer(i.e.focusing feature)is one of most important specifications of therapeutic ultrasound system.It should be characterized before delivery and in routine maintenance.Currently,the acoustic pressure is measured by using common hydrophone.However,the measurement of high acoustic pressure is limited,and the acoustic power meter with large range is expensive.Instead,the surface vibration measurement using acoustic holography method can be used to obtain the planar distribution at a low acoustic pressure and then indirectly reconstruct the focal area at high acoustic pressure.In order to evaluate the accuracy of acoustic holography method,the acoustic field at low pressure is measured and reconstructed,and the power and pressure errors between this method and the measurements using hydrophone,as well as the error sources,are analyzed.The results have demonstrated that the reconstruct acoustic field using acoustic holography method is consistent with the measurement result by using hydrophone,and so it is possible to use this method for characterizing the performance of transducer working at high acoustic pressure.

关 键 词：治疗超声 换能器 水听器 表面振动模式 声全息法 

分 类 号：O426[理学—声学]