Porat Amir, Andresen Esben Ravn, Rigneault Hervé, Oron Dan, Gigan Sylvain, Katz Ori
Opt Express. 2016 Jul 25;24(15):16835-55. doi: 10.1364/OE.24.016835.
Flexible fiber-optic endoscopes provide a solution for imaging at depths beyond the reach of conventional microscopes. Current endoscopes require focusing and/or scanning mechanisms at the distal end, which limit miniaturization, frame-rate, and field of view. Alternative wavefront-shaping based lensless solutions are extremely sensitive to fiber-bending. We present a lensless, bend-insensitive, single-shot imaging approach based on speckle-correlations in fiber bundles that does not require wavefront shaping. Our approach computationally retrieves the target image by analyzing a single camera frame, exploiting phase information that is inherently preserved in propagation through convnetional fiber bundles. Unlike conventional fiber-based imaging, planar objects can be imaged at variable working distances, the resulting image is unpixelated and diffraction-limited, and miniaturization is limited only by the fiber diameter.
柔性光纤内窥镜为在传统显微镜无法触及的深度进行成像提供了一种解决方案。当前的内窥镜在远端需要聚焦和/或扫描机制，这限制了小型化、帧率和视野。基于波前整形的无透镜替代解决方案对光纤弯曲极其敏感。我们提出了一种基于光纤束中散斑相关性的无透镜、对弯曲不敏感的单次成像方法，该方法不需要波前整形。我们的方法通过分析单个相机帧，利用在通过传统光纤束传播过程中固有保留的相位信息，以计算方式检索目标图像。与传统的基于光纤的成像不同，平面物体可以在可变工作距离下成像，所得图像是无像素化且受衍射限制的，并且小型化仅受光纤直径限制。
