Zhang Yunping, Zhu Yanmin, Lam Edmund Y
Appl Opt. 2022 Feb 10;61(5):B111-B120. doi: 10.1364/AO.444856.
Volumetric reconstruction of a three-dimensional (3D) particle field with high resolution and low latency is an ambitious and valuable task. As a compact and high-throughput imaging system, digital holography (DH) encodes the 3D information of a particle volume into a two-dimensional (2D) interference pattern. In this work, we propose a one-stage network (OSNet) for 3D particle volumetric reconstruction. Specifically, by a single feed-forward process, OSNet can retrieve the 3D coordinates of the particles directly from the holograms without high-fidelity image reconstruction at each depth slice. Evaluation results from both synthetic and experimental data confirm the feasibility and robustness of our method under different particle concentrations and noise levels in terms of detection rate and position accuracy, with improved processing speed. The additional applications of 3D particle tracking are also investigated, facilitating the analysis of the dynamic displacements and motions for micro-objects or cells. It can be further extended to various types of computational imaging problems sharing similar traits.
对三维（3D）粒子场进行高分辨率、低延迟的体积重建是一项艰巨而有价值的任务。作为一种紧凑且高通量的成像系统，数字全息术（DH）将粒子体积的3D信息编码为二维（2D）干涉图样。在这项工作中，我们提出了一种用于3D粒子体积重建的单阶段网络（OSNet）。具体而言，通过单个前馈过程，OSNet可以直接从全息图中检索粒子的3D坐标，而无需在每个深度切片进行高保真图像重建。来自合成数据和实验数据的评估结果证实了我们的方法在不同粒子浓度和噪声水平下，在检测率和位置精度方面的可行性和鲁棒性，同时提高了处理速度。还研究了3D粒子跟踪的其他应用，有助于分析微观物体或细胞的动态位移和运动。它可以进一步扩展到具有相似特征的各种类型的计算成像问题。
