Compact fiber-based multi-photon endoscope working at 1700 nm

Area of Science:

• Biomedical Optics
• Medical Imaging
• Endoscopy

Background:

• Advanced imaging techniques are crucial for minimally invasive diagnostics.
• Current endoscopic methods face limitations in imaging depth and resolution within biological tissues.

Purpose of the Study:

• To design and evaluate a compact multi-photon endoscope for enhanced in-vivo imaging.
• To achieve deeper tissue penetration and higher resolution imaging compared to existing technologies.

Main Methods:

• Development of a compact endoscope probe utilizing a piezoelectric scanning tube.
• Integration of a miniature objective lens with a long working distance and high numerical aperture (NA ≈ 0.5).
• Employment of a 1700 nm wavelength femtosecond fiber laser for excitation to minimize scattering and water absorption.

Main Results:

• Demonstration of third harmonic generation (THG/SHG) and three-photon excitation fluorescence (3PEF) imaging.
• Achieved imaging with a large field of view (> 400 μm) and high lateral resolution (2.2 μm).
• The system successfully increased imaging depth due to the chosen wavelength and optical design.

Conclusions:

• The compact multi-photon endoscope offers a promising tool for in-vivo imaging.
• Its capabilities provide a potential alternative to traditional surgical biopsies for diagnostic purposes.
• The design facilitates minimally invasive procedures with high-quality imaging.