Turnbull D H, Foster F S
Dept. of Med. Biophys., Toronto Univ., Ont.
IEEE Trans Ultrason Ferroelectr Freq Control. 1992;39(4):464-75. doi: 10.1109/58.148536.
Some of the problems of developing a two-dimensional (2-D) transducer array for medical imaging are examined. The fabrication of a 2-D array material consisting of lead zirconate titanate (PZT) elements separated by epoxy is discussed. Ultrasound pulses and transmitted radiation patterns from individual elements in the arrays are measured. A diffraction theory for the continuous wave pressure field of a 2-D array element is generalized to include both electrical and acoustical cross-coupling between elements. This theory can be fit to model the measured radiation patterns of 2-D array elements, giving an indication of the level of cross-coupling in the array, and the velocity of the acoustic cross-coupling wave. Improvements in bandwidth and cross-coupling resulting from the inclusion of a front acoustic matching layer are demonstrated, and the effects of including a lossy backing material on the array are discussed. A broadband electrical matching network is described, and pulse-echo waveforms and insertion loss from a 2-D array element are measured.
研究了用于医学成像的二维（2-D）换能器阵列开发中的一些问题。讨论了由环氧树脂隔开的锆钛酸铅（PZT）元件组成的二维阵列材料的制造。测量了阵列中各个元件的超声脉冲和发射辐射方向图。将二维阵列元件连续波压力场的衍射理论进行了推广，以包括元件之间的电交叉耦合和声交叉耦合。该理论可用于拟合二维阵列元件的测量辐射方向图，从而表明阵列中的交叉耦合水平以及声交叉耦合波的速度。展示了包含前声学匹配层后带宽和交叉耦合的改善情况，并讨论了包含有损背衬材料对阵列的影响。描述了一种宽带电匹配网络，并测量了二维阵列元件的脉冲回波波形和插入损耗。
