Automatic spectral calibration for polarization-sensitive optical coherence tomography.

Area of Science:

• Optical Coherence Tomography
• Biomedical Optics
• Metrology

Background:

• Accurate wavelength assignment is crucial for Fourier domain polarization-sensitive optical coherence tomography (FD-PS-OCT).
• Miscalibration between horizontal (H) and vertical (V) polarization channels broadens the axial point spread function and introduces polarization artifacts.
• Existing calibration methods may lack accuracy or applicability across different spectral profiles.

Purpose of the Study:

• To develop an automatic spectral calibration method for FD-PS-OCT.
• To accurately map wavenumbers (kH and kV) between orthogonal polarization channels.
• To enhance the reliability and accuracy of FD-PS-OCT imaging.

Main Methods:

• Proposes an automatic spectral calibration by optimizing the calibration coefficient between kH and kV.
• Involves a rough calibration step to establish wavelength-to-pixel relationships for each channel.
• Employs precise calibration using cross-correlation of A-line signals to align interferograms in the same k-space.
• Validates the method through simulations and experimental implementations.

Main Results:

• The proposed automatic method achieves higher calibration accuracy compared to the peaks method.
• Demonstrates suitability for both Gaussian and non-Gaussian spectral profiles.
• Effectively reduces axial point spread function broadening and polarization artifacts.

Conclusions:

• The developed automatic spectral calibration method offers a robust solution for FD-PS-OCT.
• It improves calibration accuracy and broadens applicability across various spectral types.
• This advancement contributes to more reliable and artifact-free PS-OCT imaging.