Autocorrelation artifacts in optical coherence tomography and interferometric synthetic aperture microscopy

Area of Science:

• Biomedical Optics
• Microscopy
• Signal Processing

Background:

• Optical coherence tomography (OCT) is an imaging technique that provides cross-sectional views of biological tissues.
• Interferometric synthetic aperture microscopy (ISAM) processing allows for computational refocusing of OCT data.
• Traditionally, en face planes in OCT data that are out of focus are difficult to correct.

Purpose of the Study:

• To investigate the effect of ISAM processing on autocorrelation artifacts in OCT data.
• To demonstrate that computational focusing of en face planes in OCT data can also lead to defocusing of artifacts.
• To validate these findings through experimental and simulation methods.

Main Methods:

• Interferometric synthetic aperture microscopy (ISAM) processing applied to optical coherence tomography (OCT) data.
• Computational focusing of en face planes.
• Analysis of autocorrelation artifacts generated during Fourier-domain data collection.
• Experimental validation and numerical simulations.

Main Results:

• ISAM processing enables computational focusing of previously out-of-focus en face planes in OCT images.
• This image focusing process simultaneously induces a defocusing effect on autocorrelation artifacts.
• The observed defocusing of artifacts was confirmed through both experimental measurements and computational simulations.

Conclusions:

• Computational focusing using ISAM in OCT is effective for improving image quality by correcting out-of-focus planes.
• A key consequence of this focusing is the mitigation of autocorrelation artifacts.
• The findings highlight a dual effect of ISAM processing, offering benefits for both image clarity and artifact reduction in OCT.