Optically computed compressive OCT for ultra-high speed phase-resolved dynamic imaging

项目摘要 本研究的目的是研究光学计算压缩光学相干层析成像（OCC- OCT）技术用于超高速相位分辨动态成像。光学相干断层扫描（OCT）是一种交叉- 基于低相干光干涉测量的截面成像模式。OCT已被用于成像机械运动 在细胞和组织水平上用于各种生物医学应用。然而，最先进的OCT技术并不 提供足够高的时空分辨率来对正面平面或其他任意2D平面进行成像，这限制了其 研究许多生物学上重要的动态事件的能力。在这里，我们提出了一种OCC-OCT技术， 通过利用创新的光学计算策略进行快照阶段， 分辨成像为了实现深度分辨率和相位灵敏度，OCC-OCT系统使用硬件光学传感器。 计算模块，用于计算干涉光谱与所选择的傅立叶基函数之间的内积。在 此外，光学计算模块的输出在压缩的框架内被硬件压缩， 感应数字图像处理设备（DMD）在相机的曝光时间期间施加一组随机空间掩模。 给定用于调制的已知随机图案，在以下框架内重建高速场景： 压缩感测通过促进稀疏性。OCC-OCT具有前所未有的时空精度， 分析动力现象（A（r，t））的时间演化（Δ A（r，t）/Δ t）和空间传播（Δ A（r，t））， 是建立数学模型以揭示生物系统中动力学事件的潜在机制的关键。 在本项目中，OCC-OCT系统将被开发和评估。成像系统将用于在空间上执行 解析动态成像和3D细胞跟踪。OCC-OCT有望推动生物光子学的许多领域， 包括光学相干弹性成像、光学相干血管造影、光遗传学和神经活动成像、3D 跟踪未标记的细胞等。

Project Summary The objective of this study is to investigate an optically computed compressive optical coherence tomography (OCC- OCT) technology for ultra-high speed phase-resolved dynamic imaging. Optical coherence tomography (OCT) is a cross- sectional imaging modality based on low coherence light interferometry. OCT has been used to image mechanical motion at cellular and tissue level for various biomedical applications. However, the state-of-the-art OCT technology does not provide sufficiently high spatiotemporal resolution to image en face plane or other arbitrary 2D planes, which limits its capability to study many biologically significant dynamic events. Here we propose an OCC-OCT technology that tracks subtle motion within an extended field of view, by utilizing an innovative optical computation strategy for snap shot phase resolved imaging. To achieve depth resolution and phase sensitivity, the OCC-OCT system uses a hardware optical computation module to calculate the inner product between interferometric spectra and a chosen Fourier basis function. In addition, the output of the optical computation module is hardware compressed within the framework of compressive sensing. A digital micromirror device (DMD) imposes a set of random spatial masks during the camera’s exposure time. Given the known random pattern used for modulation, high speed scenes are reconstructed within the framework of compressive sensing by promoting sparsity. With unprecedented spatiotemporal accuracy, OCC-OCT enables quantitative analysis of dynamic phenomenon (A(r, t)) on its temporal evolution (∂A(r, t)/∂t) and spatial propagation (∇A(r, t)), which is crucial to establish mathematical models to reveal the underlying mechanisms of dynamic events in biological systems. In this project, OCC-OCT system will be developed and evaluated. The imaging system will be used to perform spatially resolved dynamic imaging and 3D cell tracking. OCC-OCT is anticipated to advance many fields of biophotonics, including optical coherence elastography, optical coherence angiography, optogenetics and neural activity imaging, 3D tracking of unlabeled cells, etc.