Institut Langevin, Ecole Superieure de Physique et de Chimie Industrielles, ParisTech, CNRS Unité Mixte de Recherche 7587, 1 Rue Jussieu, 75005 Paris, France.
J Acoust Soc Am. 2013 Aug;134(2):1049-54. doi: 10.1121/1.4812260.
Acoustic focusing experiments usually require large arrays of transducers. It has been shown by Etaix et al. [J. Acoust. Soc. Am. 131, 395-399 (2012)] that the use of a cavity allows reducing this number of transducers. This paper presents experiments with Duralumin plates (the cavities) containing scatterers to improve the contrast of focusing. The use of a scatterer array in the plate allows increasing the modal density at given frequencies. The scatterers used are membranes and buttons that are manufactured in Duralumin plates. Their resonances are studied both experimentally and numerically. Such scatterers present the advantage of having a tunable frequency resonance, which allows controlling the frequencies at which the modal density increases. The dispersion relations of plates with scatterer array show high modal density at given frequencies. Finally acoustic focusing experiments in air, using these plates, are compared to the ones of simple duralumin plates demonstrating the improvement of contrast. Acoustic source localization is also realized using these plates.
声聚焦实验通常需要大量的换能器阵列。Etaix 等人已经表明[J. Acoust. Soc. Am. 131, 395-399 (2012)]，使用腔可以减少换能器的数量。本文介绍了在含有散射体的硬铝板（腔）中进行的实验，以提高聚焦的对比度。在板中使用散射体阵列可以在给定频率下增加模态密度。使用的散射体是在硬铝板上制造的膜片和按钮。它们的共振通过实验和数值研究进行了研究。这种散射体的优点是具有可调谐频率的共振，这允许控制模态密度增加的频率。带有散射体阵列的板的频散关系在给定频率下显示出高模态密度。最后，使用这些板在空气中进行了声聚焦实验，与简单的硬铝板进行了比较，证明了对比度的提高。还使用这些板实现了声源定位。
