基于自相位调制光谱选择驱动的无标记自发荧光多倍频显微镜系统  

Simultaneous label-free autofluorescence-multiharmonic microscopy driven by femtosecond sources based on self-phase modulation enabled spectral selection

作　　者：王晓英 邢宇婷 陈润植 贾雪琦 吴继华 江进 李连勇 常国庆 Wang Xiao-Ying;Xing Yu-Ting;Chen Run-Zhi;Jia Xue-Qi;Wu Ji-Hua;Jiang Jin;Li Lian-Yong;Chang Guo-Qing(Department of Gastroenterology,Strategic Support Force Medical Center,Beijing 100101,China;Key Laboratory of Optical Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;Department of Pathology,Strategic Support Force Medical Center,Beijing 100101,China)

机构地区：[1]战略支援部队特色医学中心,消化科,北京100101 [2]中国科学院物理研究所,光物理重点实验室,北京100190 [3]战略支援部队特色医学中心,病理科,北京100101

出　　处：《物理学报》2022年第10期115-122,共8页Acta Physica Sinica

基　　金：战略支援部队特色医学中心医药卫生临床创新探索课题(批准号:19ZX40);国家自然科学基金(批准号:11774234);用于三维生物模型大深度和高精度成像的新型多光子显微镜研制项目(批准号:YJKYYQ20190034)资助的课题。

摘　　要：由飞秒激光驱动的非线性光学显微镜技术在医学组织成像中具有很多独特的优势,包括多种成像模态、高对比度、高分辨率和无标记的深层光学切片能力等.由于缺乏波长可灵活调谐的飞秒激发光源,导致在多模态成像的同时难以兼顾每种模态的对比度,从而制约了非线性光学显微镜在医学诊断中的广泛应用.本文采用基于自相位调制光谱选择的光纤激光光源,获得了中心波长在990—1110 nm范围内可调谐的高能量飞秒脉冲,并用于驱动非线性光学显微镜.采用990 nm的飞秒脉冲,通过双光子激发荧光和二倍频对胃组织成像,进一步结合图像拼接技术成功获得了胃组织的双模态大视场图像;利用1110 nm的飞秒脉冲,实现了无标记自发荧光多倍频显微镜技术,同时高效激发了胃组织的双光子激发荧光、三光子激发荧光、二倍频和三倍频信号,获得了胃组织的多模态图像.Nonlinear optical microscopy technique has unique advantages in tissue imaging,such as enhanced contrast,high resolution,and label-free deep optical sectioning capabilities.Nonlinear optical microscopy also has multiple imaging modalities,corresponding to various components in biological tissues.Unfortunately,its wide applications are hindered due to the lack of broadly tunable femtosecond sources designed for driving multimodalities simultaneously.To solve this challenge,we propose a new wavelength conversion approach—self-phase modulation(SPM) enabled spectral selection,dubbed as SESS.The SESS employs SPM to broaden the input spectrum in a short fiber,and the broadened spectrum features well-isolated spectral lobes.Using the suitable optical filters to select the outermost spectral lobes produces nearly transform-limited femtosecond pulses.In this work,we demonstrate a fiber-optic SESS source for multimodal nonlinear optical microscopy.Based on a 43-MHz Yb-fiber laser,this SESS source can emit 990-nm,84-fs pulses with >5-nJ energy and ~84-fs pulse duration;it can also produce 1110-nm,48-fs pulses with 15-nJ energy.The 990-nm pulses are used to drive two-photon excitation fluorescence of many important fluorophores and secondharmonic generation microscopy,which,combined with image splicing technology,enables us to obtain a large field of view image of the gastric tissue.We also employ the 1110-nm pulses to drive simultaneous label-free autofluorescence-multiharmonic microscopy for multimodal imaging of gastric tissue.Two-photon excitation fluorescence,three-photon excitation fluorescence,second-harmonic generation and third-harmonic generation signals of gastric tissue are simultaneously excited efficiently.Such a multimodal nonlinear optical microscopy driven by SESS sources becomes a powerful tool in biomedical imaging.

关 键 词：光纤激光器 自相位调制 非线性光学显微镜 

分 类 号：TH742.65[机械工程—光学工程]