在散射中聚焦过程的自画像：I. 在复杂介质中波包的时空成像
Self-Portrait of the Focusing Process in Speckle: I. Spatio-Temporal Imaging of Wave Packets in Complex Media
AI总结：
本文提出利用散射体作为虚拟麦克风，通过矩阵成像技术监测波包在复杂介质中的时空传播，以揭示聚焦过程的缺陷并提升成像性能。
摘要：
本文是系列三篇文章中第一篇，探讨如何利用散射进行成像。散射是由随机分布的未分辨散射体产生的复杂干涉波场。在本文中，我们展示了如何利用这些散射体作为虚拟麦克风，监测波包在介质中的时空传播。为此，矩阵成像的概念尤其有用。它涉及在标准波束成形过程中解耦发射和接收焦点斑点的位置。通过用输出焦点斑点扫描波场，该斑点则充当虚拟换能器，可以成像波包在介质中的时空演化。这一独特的可观察量将允许我们突出聚焦过程的缺陷，特别是由强散射层引起的失焦和回声。作为概念验证，我们将考虑在模拟组织的仿生材料上的超声实验。在接下来的两篇文章中，我们将展示如何利用这一可观察量来补偿这些阻碍波聚焦和成像的现象，所有波物理领域中的波聚焦和成像都会受到这些现象的阻碍。我们的方法确实可以广泛应用于除超声波以外的其他类型的波，因为多元素技术允许测量反射矩阵。
英文摘要：
This is the first article in a series of three dealing with the exploitation of speckle for imaging purposes. Speckle is the complex interference wave-field produced by a random distribution of un-resolved scatterers. In this paper, we show how these scatterers can be used as virtual microphones to monitor the spatio-temporal propagation of a wave-packet inside the medium. To do so, the concept of matrix imaging is particularly useful. It consists in decoupling the location of the transmitted and received focal spots in a standard beamforming process. By scanning the wave-field with the output focal spot that then acts as a virtual transducer, one can image the spatio-temporal evolution of the wave-packet inside the medium. This unique observable will allow us to highlight the imperfections of the focusing process, in particular the defocus and reverberations induced by a strong aberrating layer. As a proof-of-concept, we will consider ultrasound experiments on tissue-mimicking phantoms. In the next two papers, we will show how this observable can be leveraged to compensate for these phenomena that hamper wave focusing and imaging in all fields of wave physics. Our method is indeed broadly applicable to different types of waves beyond ultrasound for which multi-element technology allows a reflection matrix to be measured.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
