High-resolution, lensless endoscope based on digital scanning through a multimode optical fiber.

Area of Science:

• Biomedical Engineering
• Optical Imaging
• Microscopy

Background:

• Traditional endoscopes face limitations in diameter and resolution.
• Minimally invasive imaging requires advanced optical techniques.
• Modal scrambling in optical fibers hinders high-resolution imaging.

Purpose of the Study:

• To develop an ultra-thin rigid endoscope for high-resolution imaging.
• To overcome modal scrambling in passive multimode optical fibers.
• To enable minimally invasive medical diagnosis through cellular imaging.

Main Methods:

• Utilized a passive multimode optical fiber for endoscope construction (450 μm diameter).
• Employed digital phase conjugation to control light propagation and focus.
• Exploited maximum available fiber modes for imaging.

Main Results:

• Achieved sub-micron resolution imaging of neuronal cells.
• Acquired high-quality fluorescence images.
• Demonstrated effective focusing and scanning of laser light at the distal end.

Conclusions:

• The ultra-thin endoscope offers a promising solution for minimally invasive medical imaging.
• High-resolution cellular imaging can be achieved via direct tissue penetration.
• The system's performance in fluorescence collection, resolution, and field of view was validated.