Øygard Sigrid H, Audoin Mélanie, Austeng Andreas, Thomsen Erik V, Stuart Matthias B, Jensen Jørgen A
Department of Health Technology, Technical University of Denmark, DK-2800 Lyngby, Denmark.
Department of Informatics, University of Oslo, Gaustadalléen 23B, 0373 Oslo, Norway.
J Acoust Soc Am. 2022 May;151(5):3207. doi: 10.1121/10.0010528.
Using a diverging lens on a row-column array (RCA) can increase the size of its volumetric image and thus significantly improve its clinical value. Here, a ray tracing method is presented to predict the position of the transmitted wave so that it can be used to make beamformed images. The usable transmitted field-of-view (FOV) is evaluated for a lensed 128 + 128 element RCA by comparing the theoretic prediction of the emitted wavefront position with three-dimensional (3D) finite element simulation of the emitted field. The FOV of the array is found to be 122° ± 2° in the direction orthogonal to the emitting elements and 28.5°-51.2°, depending on depth and element position, for the direction lying along the element. Moreover, the proposed ray tracing method is compared with a simpler thin lens model, and it is shown that the improved accuracy of the proposed method can increase the usable transmitted FOV up to 25.1°.
在行列阵列（RCA）上使用发散透镜可以增大其体积图像的尺寸，从而显著提高其临床价值。在此，提出了一种光线追踪方法来预测透射波的位置，以便用于生成波束形成图像。通过将发射波前位置的理论预测与发射场的三维（3D）有限元模拟进行比较，评估了带透镜的128 + 128元件RCA的可用透射视野（FOV）。发现阵列在与发射元件正交的方向上的FOV为122°±2°，在沿元件的方向上，FOV为28.5° - 51.2°，具体取决于深度和元件位置。此外，将所提出的光线追踪方法与一个更简单的薄透镜模型进行了比较，结果表明所提方法提高的精度可使可用透射FOV增加多达25.1°。
