All-fiber wavelength swept ring laser based on Fabry-Perot filter for optical frequency domain imaging

Area of Science:

• Laser Engineering
• Optical Engineering
• Biomedical Optics

Background:

• High repetition rate, broad sweep range, and long coherence length wavelength swept lasers are crucial for advanced applications like frequency-domain optical coherence tomography (FD-OCT).
• Existing swept laser technologies are often complex, expensive, and rely on proprietary materials or devices, limiting their accessibility and widespread adoption.

Purpose of the Study:

• To demonstrate a simplified and cost-effective ring resonator configuration for wavelength swept lasers.
• To enable high-performance FD-OCT imaging using a laser built from readily available components.

Main Methods:

• Developed a simplified ring resonator laser design.
• Implemented isolation against bidirectional operation.
• Configured the intracavity filter's sweep range to exceed its free spectral range.
• Utilized readily available materials for construction.

Main Results:

• Demonstrated a robust and stable laser with 240 kHz operation, a 125 nm sweep range, and >70 mW average output power.
• Achieved high-quality frequency-domain optical coherence tomography (FD-OCT) imaging.
• The laser design is straightforward to construct at a low total cost.

Conclusions:

• The simplified ring resonator configuration offers a practical and affordable solution for advanced wavelength swept lasers.
• This design overcomes the limitations of complexity and cost associated with previous technologies.
• The laser is suitable for high-performance FD-OCT and can be optimized for various operating specifications.