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本文介绍的功率超声聚焦波束发生器是采用六个面积相等的同心圆环形平面换能器作为声发射基阵。当改变对每个圆环的电激励信号从外向内递增的时延，就能实现改变等效球面换能器的曲率半径，从而达到可变聚焦焦距的目的。本系统经聚焦后在声焦点处的声束宽度（按－６分贝计）与平面换能器的声束宽度相比，声束缩小了大约５倍。本装置在水槽里工作时，可明显看到在声焦点附近由于空化所引起的气泡群。根据气泡群的分布可以直接观察到聚焦波束的大致形状。 本文还在理论上导出了由六个圆环构成的等效球面换能器在空间任意点Ｑ的声压表示式，由此可以计算出超声聚焦声场的形状，为确定时延系统的设计参数提供了依据。
This article describes the power ultrasonic focus beam generator is the use of six equal-area concentric circular planar transducer as the acoustic emission matrix. The change of the radius of curvature of the equivalent spherical transducer to achieve the variable focus focal length can be achieved by changing the delay of increasing the electrical excitation signal of each ring from the outside to the inside. The acoustic beam width (by -6 dB) at the focal point of focus of the system after focusing is reduced by about 5 times compared to the beam width of the planar transducer. When this device is working in the sink, it is obvious that the bubble group caused by cavitation near the sound focus. The approximate shape of the focused beam can be directly observed from the distribution of bubble groups. In this paper, we also derive the sound pressure representation of an equivalent spherical transducer composed of six rings in arbitrary space Q theoretically, so as to calculate the shape of the ultrasound focused sound field. In order to determine the design parameters of the time delay system Provided the basis.