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Updated: Jun 26, 2026
13:49
High-resolution Fiber-optic Microendoscopy for in situ Cellular Imaging
Published on: January 11, 2011
Experimental and theoretical analysis of core-to-core coupling on fiber bundle imaging
Xianpei Chen1, Kristen Lantz Reichenbach, Chris Xu
1School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA. cx10@cornell.edu
Optics Express
|December 24, 2008
Summary
Image fiber bundles used in flexible endoscopes experience significant core-to-core coupling, impacting resolution. Increasing core-cladding index contrast can reduce coupling and improve imaging performance.
Area of Science:
- Optics and Photonics
- Biomedical Imaging
- Materials Science
Background:
- Flexible endoscopes rely on coherent fiber bundles for in vivo imaging.
- High core density in fiber bundles is crucial for high-resolution imaging.
- Close core spacing can lead to unwanted core-to-core coupling.
Purpose of the Study:
- To investigate the extent and impact of core-to-core coupling in imaging fiber bundles.
- To analyze the dependence of coupling on illumination wavelength and polarization.
- To propose methods for improving fiber bundle performance for medical imaging.
Main Methods:
- Numerical simulations of light propagation in fiber bundles.
- Experimental validation using fabricated fiber bundles.
- Analysis of image resolution in relation to core coupling.
Main Results:
- Significant core-to-core coupling exists even with structural nonuniformities.
- Coupling strength is highly dependent on wavelength and polarization.
- Image resolution is limited by both core density and inter-core coupling.
Conclusions:
- Random structural nonuniformities do not eliminate core-to-core coupling in imaging fiber bundles.
- Inter-core coupling is a critical factor affecting achievable resolution.
- Increasing core-cladding index contrast is a promising strategy to reduce coupling and enhance imaging capabilities.
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