Abstract

The focusing principle and acoustic field characteristics of curved array probe are studied. Delay laws are first computed in the same way as linear array probe, and its effects on the axial acoustic pressure distributions are quantitatively examined. It is shown that the maximum points of axial acoustic pressure occur at positions deviating from the predefined focal depths. To further analyze the focusing principle of curved array probe, simulations of acoustic field are conducted under different settings of focal depth and active aperture size. It reveals that the circular array profile and the inconsistent electronic delay laws make the pulsed ultrasonic waves unable to constructively interfere at target positions. Subsidiary beams arise and further interfere with the axial acoustic pressure distributions of the main beam. To control the transmitted acoustic field, and thus customize the inspection strategy, an optimized delay law calculation scheme is proposed. The good behavior is well validated both by theoretical calculation and experimental examination.

中文翻译：

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弯曲阵列探头的声场表征与优化

摘要

研究了曲面阵列探头的聚焦原理和声场特性。首先以与线性阵列探头相同的方式计算延迟定律，然后定量检查其对轴向声压分布的影响。结果表明，轴向声压的最大点出现在偏离预定焦深的位置。为了进一步分析曲面阵列探头的聚焦原理，在焦深和有效孔径大小的不同设置下进行了声场模拟。它揭示了圆形阵列轮廓和不一致的电子延迟定律使脉冲超声波无法在目标位置相长干涉。辅助束出现并进一步干扰主束的轴向声压分布。为了控制传输的声场，从而定制检查策略，提出了一种优化的延迟定律计算方案。理论计算和实验检验都很好地证明了该良好行为。