Spatial distortions in swept source optical coherence tomography due to lateral scanning

Area of Science:

• Biomedical Optics
• Optical Coherence Tomography
• Metrology

Background:

• Swept source optical coherence tomography (SS-OCT) is a key imaging modality.
• Lateral scanning in SS-OCT can introduce artifacts in measurements.
• Understanding these artifacts is crucial for accurate imaging.

Purpose of the Study:

• To investigate errors in axial distance measurements and contour deviations in SS-OCT.
• To analyze the impact of lateral scanning on SS-OCT image accuracy.
• To establish a method for predicting swept source tuning direction.

Main Methods:

• Development of a theoretical model to explain measurement errors.
• Experimental validation of the theoretical model.
• Analysis of Doppler shift frequency in relation to lateral scanning parameters.

Main Results:

• Errors and deviations are directly related to the Doppler shift frequency from lateral scanning.
• Fewer sweeps per lateral scanning interval result in larger errors.
• The sign of contour errors correlates with the spectral sweeping direction.

Conclusions:

• Lateral scanning introduces predictable errors in SS-OCT axial measurements and contours.
• Doppler shift is the underlying cause of these scanning-induced artifacts.
• Spectral sweeping direction can predict swept source tuning without an optical spectrum analyzer.