This code is given as an example as a supplement to the 2023 manuscript "Needle guidance with Doppler-tracked polarization-sensitive optical coherence tomography"
by Danielle J. Harper, Yongjoo Kim, Alejandra Gomez-Ramirez and Benjamin J. Vakoc.

It is not actively maintained, but users are welcome to contact Danielle J. Harper (djharper@mgh.harvard.edu) should they have any questions regarding the code.

"get_phase_diff.m" allows the calculation of phase difference from raw phase information obtained from an OCT interferogram.
"doppler_needle_vis.m" uses pre-stored phase differences generated by "get_phase_diff.m" and creates surface-referenced maps of intensity, phase retardation, and optic axis as the needle moves.