All fiber optics circular-state swept source polarization-sensitive optical coherence tomography.

Area of Science:

• Biomedical Optics
• Optical Coherence Tomography
• Fiber Optics

Background:

• Polarization-sensitive optical coherence tomography (PS-OCT) provides valuable information about tissue birefringence.
• Traditional PS-OCT systems often rely on bulk optical components, limiting miniaturization and robustness.
• Developing compact and portable PS-OCT systems is crucial for broader clinical adoption.

Purpose of the Study:

• To propose and experimentally verify a novel all-fiber circular-state (CS) swept source (SS) polarization-sensitive optical coherence tomography (PS-OCT) system.
• To demonstrate the feasibility of replacing bulk optics with fiber-optic components for enhanced system portability and reduced alignment sensitivity.
• To investigate the system's performance, including accuracy, resolution, and robustness to environmental factors like fiber bending.

Main Methods:

• Construction of a CS SS PS-OCT system using entirely polarization-maintaining fiber optics.
• Implementation of a calibration scheme to substitute bulk quarter-wave plates with fiber optic polarization controllers.
• Development and application of a numerical dispersion compensation method to improve axial resolution and signal-to-noise ratio.
• Investigation of the influence of fiber bending on phase retardation and fast-axis angle measurements.

Main Results:

• Successful realization of an all-fiber CS SS PS-OCT system.
• Demonstration of comparable accuracy to bulk optics systems with reduced alignment requirements.
• Numerical dispersion compensation enhanced axial resolution and signal-to-noise ratio.
• In vivo imaging of human fingertip and nail was successfully achieved using a linear scanning probe.

Conclusions:

• The developed all-fiber CS SS PS-OCT system is compact, portable, and accurate.
• The system's design facilitates easier integration into clinical settings, such as endoscopic applications.
• The findings suggest this technology can advance the development of practical PS-OCT instruments for medical diagnostics.