High-resolution endomicroscopy with a spectrally encoded miniature objective.

Area of Science:

• Biomedical Optics
• Microscopy Engineering

Background:

• Fiber bundle endomicroscopy is crucial for minimally invasive imaging.
• Limited imaging cores in fiber bundles restrict spatial sampling.
• Existing techniques face challenges in achieving high-resolution imaging.

Purpose of the Study:

• To develop a miniature objective to overcome fiber bundle sampling limitations.
• To enhance spatial resolution in fiber bundle endomicroscopy.
• To utilize spectral encoding for improved imaging performance.

Main Methods:

• Fabrication of a custom miniature objective (2.4 mm diameter, 0.3 NA).
• Coupling the objective to a fiber bundle.
• Application of the spectral encoding concept.
• Validation using a USAF resolution target and ex vivo tissue samples.

Main Results:

• The miniature objective achieved a maximum spatial resolution of 2 μm.
• Spectral encoding significantly improved image resolution and detail.
• Validated performance on resolution targets and biological samples.
• Demonstrated overcoming of the fiber bundle's inherent sampling threshold.

Conclusions:

• The custom miniature objective effectively enhances spatial sampling in fiber bundle endomicroscopy.
• Spectral encoding is a viable strategy to achieve higher resolution in fiber imaging.
• This technology offers improved capabilities for minimally invasive diagnostic and surgical imaging.