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bioRxiv · 10.1101/406108

Aperture Phase Modulation with Adaptive Optics: A Novel Approach for Speckle Reduction and Structure Extraction in Optical Coherence Tomography

Zhang, P.·Manna, S. K.·Miller, E. B.·Jian, Y.·Meleppat, R. K.·Sarunic, M. V.·Pugh, E. N.·Zawadzki, R. J.
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Abstract

AbstractSpeckle is an inevitable consequence of the use of coherent light in optical coherence tomography (OCT), and often acts as noise that obscures micro-structures of biological tissue. We here present a novel method of suppressing speckle noise intrinsically compatible with adaptive optics (AO) in OCT system: by modulating the phase inside the imaging system pupil aperture with a segmented deformable mirror, thus producing minor perturbations in the point spread function (PSF) to create un-correlated speckle pattern between B-scans, and further averaging to wash out the speckle but maintain the structures. It is a well-controlled and universal method which can efficiently determine the optimal range of phase modulation that minimizing speckle noise while maximizing image resolution and signal strength for different systems and/or samples. As an active method, its effectiveness and efficiency were demonstrated by both ex-vivo non-biological and in-vivo biological applications.

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Zhang, P., Manna, S. K., Miller, E. B., Jian, Y., Meleppat, R. K., Sarunic, M. V., Pugh, E. N., Zawadzki, R. J.. 2018-08-31. Aperture Phase Modulation with Adaptive Optics: A Novel Approach for Speckle Reduction and Structure Extraction in Optical Coherence Tomography. https://doi.org/10.1101/406108

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