Image transmission through multimode optical fibers has been an area of immense interests driven by the demand for miniature endoscopes in biomedicine and higher speed and capacity in telecommunications. Conventionally, a complex-valued transmission matrix is obtained experimentally to link the input and output light fields of a multimode fiber for image retrieval, which complicates the experimental setup and increases the computational complexity. Here, we report a simple and high-speed method for image retrieval based on our demonstration of a pseudo-linearity between the input and output light intensity distributions of multimode fibers. We studied the impact of several key parameters to image retrieval, including image pixel count, fiber core diameter and numerical aperture. We further demonstrated with experiments and numerical simulations that a wide variety of input binary and gray scale images could be faithfully retrieved from the corresponding output speckle patterns. Thus, it promises to be useful for highly miniaturized endoscopy in biomedicine and spatial-mode-division multiplexing in telecommunications.

中文翻译：

---

透视具有实值强度传输矩阵的多模光纤

通过多模光纤的图像传输已经成为生物医学领域对微型内窥镜的需求以及电信领域中更高速度和容量的需求所推动的领域。常规上，通过实验获得复值传输矩阵来链接多模光纤的输入和输出光场以进行图像检索，这使实验设置复杂化并增加了计算复杂性。在此，我们基于对多模光纤的输入和输出光强度分布之间的伪线性的演示，报告了一种简单且高速的图像检索方法。我们研究了几个关键参数对图像检索的影响，包括图像像素数，纤维芯直径和数值孔径。我们通过实验和数值模拟进一步证明，可以从相应的输出散斑图案中忠实地检索出各种输入的二进制和灰度图像。因此，它有望用于生物医学中的高度小型化的内窥镜检查和电信中的空间模式分割多路复用。