医用梅花形超声探头声场的分析与计算

本文根据基尔霍夫积分．推导出了用于胎儿监护的梅花形超声多普勒探头声场的具体表达式．对中心大圆晶片发射、周围六个小圆片接收，以及七个相同晶片四发三收两种典型布局的换能器，其轴上声压分布，离辐射面不同距离断面上的声压分布及不同定向平面上的远场指向性进行了数值计算．结果表明，采用四发三收式结构较一发六收式结构具有较大的优越性．计算结果与实际测试结果很好地吻合．本项研究对此类探头的研制、使用及质量评价标准的制订，具有理论指导意义．

Analyses and calculations for sound field of Plum Blossom-shaped ultrasonic transducers for medical diagnosis

In the article. concrete expressions for the sound field of a Plum Blossomshaped ultrasonic doppler transducers used for foetus monitor are deduced from Kirchhoffsintegral. For two kinds of typical transducers (central piezoelectric plate emitting, sixsmall plates recelving and four plates emitting, three plates receiving), distributions of pressure on the axis and in different cross-sections as well as the derectivities are calculated. The results indicate that the transducer of four-emitting and three-receiving has great advantages over the transducer of one emitting and six-recelvlng. Consistence between calculation we have made is reliable. The research should be valuable in designning, using and working out quality-evaluating standard for this kind of transducer.