Advances of large field-of-view two-photon microscopy system (invited)

Abstract

Two-photon microscopy (TPM) imaging has the characteristics of high resolution, natural chromatography capability and large penetration depth, and plays an important role in the imaging of living animals. How to enlarge the field-of-view (FOV) of TPM while maintaining the high resolution to monitor largescale dynamic responses in biomedical applications especially brain science, however, remains challenging. In this paper, the recent progress of large-FOV two-photon imaging technology is reviewed. The theoretical basis of achieving large-FOV TPM is elaborated from the perspective of optical invariant. Large- FOV TPM methods can be divided into three categories: FOV-edge aberration calibration with scanning relay engines, the design and manufacture of high-throughput objectives and correcting aberrations with adaptive optics. These methods have highly strengthened the capability of TPM used in large scale biomedical imaging. If further improved especially the imaging speed, large-FOV TPM will have great potential to contribute the development of life science and broaden the cognitive of large-scale biological activities. Large-FOV TPM, based on its outstanding spatial and temporal resolution, will become a powerful tool for dynamic monitoring across large-area in some applications that requires high resolution and mesoscale imaging simultaneously. 双光子显微成像具备高分辨率、天然层析能力和大穿透深度等特点，在活体动物成像中发挥着重要作用。然而，如何在维持高分辨率的条件下，扩大双光子的成像视场，来满足生物医学中对大规模动态反应的监测需求，一直以来都是光学显微成像领域的难点，也是科研关注的重点。综述了大视场双光子成像技术的研究进展。首先介绍了双光子显微成像系统的产生背景和设计原理，并从光学不变量的角度阐述了实现大视场双光子成像的理论基础。然后重点回顾了现有的几种大视场双光子成像方法,分别包括了扫描中继系统的边缘像差校准、高通量物镜的设计研发和自适应光学方法的使用。基于双光子成像的高时间和空间分辨特性，大视场双光子成像技术将成为一种在脑科学等需介观高分辨成像领域的应用中实现大区域动态监测的强有力的工具。