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Updated: Jun 22, 2026
13:49
High-resolution Fiber-optic Microendoscopy for in situ Cellular Imaging
Published on: January 11, 2011
Rigid and high-numerical-aperture two-photon fluorescence endoscope.
R Le Harzic1, I Riemann, M Weinigel
1Fraunhofer Institute of Biomedical Engineering (IBMT), Ensheimer Strasse 48, D-66386 St. Ingbert, Germany. ronan.leharzic@ibmt.fraunhofer.de
Applied Optics
|June 23, 2009
Summary
We developed a compact fiber-optic two-photon endoscope using a piezo scanner and GRIN lens. This miniaturized endoscope achieves high resolution for subcellular imaging and shows potential for in vivo applications.
Area of Science:
- Biomedical Optics
- Microscopy
- Optical Engineering
Background:
- Advanced imaging techniques are crucial for visualizing subcellular structures.
- Miniaturized endoscopes are needed for minimally invasive in vivo studies.
Purpose of the Study:
- To develop and characterize a rigid miniaturized fiber-optic two-photon endoscope.
- To assess its resolution and potential for in vivo subcellular imaging.
Main Methods:
- A compact two-axis piezo scanner system with a miniature high NA GRIN lens objective was employed.
- Photonic crystal fiber delivered ultrashort laser pulses (800 nm, up to 100 mW).
- Two-photon fluorescence was collected via multimode fiber, and the system was scanned as a whole.
Main Results:
- Lateral resolution was measured at 0.67 µm (vertical) and 1.08 µm (horizontal).
- Axial resolution was determined to be 5.8 µm.
- Fluorescence images were acquired with a 420 µm x 420 µm field of view, resolving subcellular details.
Conclusions:
- The developed endoscope is flexible, controllable, and capable of high-resolution imaging.
- It demonstrates significant potential for in vivo applications requiring subcellular detail visualization.
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