Significance: Practical implementation of acousto-optic imaging (AOI) encounters difficulties that prevent it from rapid adoption in clinical use. In many practical medical applications, the region of interest may be accessed only from one side, and using a water tank for coupling is not feasible. The solution might be to use reflection-mode imaging with an electronically scanned ultrasound (US) focus. Such an approach, however, entails considerable challenges. Aim: The possibilities of detecting and localizing light-absorbing inclusions inside turbid media by combining reflection-mode AOI conducted using a one-dimensional US array with electronic scanning of the US focus are investigated experimentally and signal processing algorithms that could be used for this purpose are introduced. Approach: We determine the speckle contrast decrease due to the acousto-optic effect as a function of the US focal point coordinates. Different signal postprocessing techniques are investigated. Results: A significant decrease in the determined speckle contrast difference values is observed due to the presence of light-absorbing inclusions. However, local minima occur in the plots only under specific conditions. Subtracting individual distributions and determining symmetry deviations allow for localizing the inclusions. Conclusions: Detection and localization of optically distinct regions are possible using the introduced approach. Signal postprocessing is required in a general case.

中文翻译：

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使用具有电子扫描焦点的一维超声阵列进行反射模式声光成像。


意义：声光成像（AOI）的实际实施遇到了困难，阻碍了其在临床应用中的快速采用。在许多实际的医疗应用中，可能仅从一侧进入感兴趣区域，并且使用水箱进行耦合是不可行的。解决方案可能是使用带有电子扫描超声（US）焦点的反射模式成像。然而，这种方法带来了相当大的挑战。目的：通过实验研究通过将使用一维 US 阵列进行的反射模式 AOI 与 US 焦点的电子扫描相结合来检测和定位混浊介质内的光吸收夹杂物的可能性，以及可用于此目的的信号处理算法被介绍。方法：我们将声光效应导致的散斑对比度降低确定为 US 焦点坐标的函数。研究了不同的信号后处理技术。结果：由于吸光夹杂物的存在，观察到所测定的散斑对比度差值显着下降。然而，局部最小值仅在特定条件下出现在图中。减去个体分布并确定对称偏差可以定位夹杂物。结论：使用所介绍的方法可以检测和定位光学不同区域。一般情况下需要进行信号后处理。