A zero-crossing detection method applied to Doppler OCT

Area of Science:

• Biomedical Optics
• Fluid Dynamics
• Signal Processing

Background:

• Doppler Optical Coherence Tomography (OCT) is crucial for non-invasive blood flow measurement.
• Accurate Doppler frequency estimation is essential for reliable velocity quantification.
• Existing methods for Doppler frequency analysis in OCT have limitations, especially in specific flow regimes.

Purpose of the Study:

• To introduce and evaluate a novel numerical method for Doppler frequency measurement in laminar flow.
• To compare the precision of the zero-crossing method against established Doppler OCT processing techniques.
• To determine the optimal application range for the zero-crossing method in velocity measurements.

Main Methods:

• A numerical method utilizing zero-crossing point detection within OCT signals was developed.
• The proposed method was applied to analyze Doppler frequency in simulated and experimental laminar flow.
• Performance was benchmarked against conventional Doppler OCT signal processing approaches.

Main Results:

• The zero-crossing method demonstrated high precision in measuring Doppler frequency for laminar flow.
• Compared to other techniques, the zero-crossing method yielded superior accuracy, especially at higher flow velocities.
• The method's effectiveness was validated under conditions of laminar fluid dynamics.

Conclusions:

• The zero-crossing detection method offers a precise and reliable approach for Doppler frequency measurement in laminar flow OCT.
• This technique provides an advantageous alternative to existing methods, particularly for characterizing higher velocity regimes.
• The findings support the broader adoption of zero-crossing analysis for enhanced Doppler OCT applications.