Throughput-Speed Product Augmentation for Scanning Fiber-Optic Two-Photon Endomicroscopy

Wenxuan Liang, Hyeon Cheol Park, Kaiyan Li, Ang Li, Defu Chen, Honghua Guan, Yuanlei Yue, Yung Tian A. Gau, Dwight E. Bergles, Ming Jun Li, Hui Lu, Xingde Li

Research output: Contribution to journalArticlepeer-review

2 Scopus citations


Compactness, among several others, is one unique and very attractive feature of a scanning fiber-optic two-photon endomicroscope. To increase the scanning area and the total number of resolvable pixels (i.e., the imaging throughput), it typically requires a longer cantilever which, however, leads to a much undesired, reduced scanning speed (and thus imaging frame rate). Herein we introduce a new design strategy for a fiber-optic scanning endomicroscope, where the overall numerical aperture (NA) or beam focusing power is distributed over two stages: 1) a mode-field focuser engineered at the tip of a double-clad fiber (DCF) cantilever to pre-amplify the single-mode core NA, and 2) a micro objective of a lower magnification (i.e., ∼ 2× in this design) to achieve final tight beam focusing. This new design enables either an 9-fold increase in imaging area (throughput) or an 3-fold improvement in imaging frame rate when compared to traditional fiber-optic endomicroscope designs. The performance of an as-designed endomicroscope of an enhanced throughput-speed product was demonstrated by two representative applications: (1) high-resolution imaging of an internal organ (i.e., mouse kidney) in vivo over a large field of view without using any fluorescent contrast agents, and (2) real-time neural imaging by visualizing dendritic calcium dynamics in vivo with sub-second temporal resolution in GCaMP6m-expressing mouse brain. This cascaded NA amplification strategy is universal and can be readily adapted to other types of fiber-optic scanners in compact linear or nonlinear endomicroscopes.

Original languageEnglish (US)
Article number9125994
Pages (from-to)3779-3787
Number of pages9
JournalIEEE transactions on medical imaging
Issue number12
StatePublished - Dec 2020


  • Biomedical optical imaging
  • biophotonics
  • endomicroscope
  • in vivo imaging
  • nonlinear optics
  • optical microscopy
  • two-photon microscopy

ASJC Scopus subject areas

  • Software
  • Radiological and Ultrasound Technology
  • Computer Science Applications
  • Electrical and Electronic Engineering


Dive into the research topics of 'Throughput-Speed Product Augmentation for Scanning Fiber-Optic Two-Photon Endomicroscopy'. Together they form a unique fingerprint.

Cite this