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arXiv · 1212.1595

Large-volume optical coherence tomography with real-time correction of geometric distortion artifacts

Sam Van der Jeught·Jan A. N. Buytaert·Adrian Bradu·Adrian Gh. Podoleanu·Joris J. J. Dirckx
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Abstract

Large-volume optical coherence tomography (OCT)-setups employ scanning mirrors and suffer from non-linear geometric distortion artifacts in which the degree of distortion is determined by the maximum angles over which the mirrors rotate. In this chapter, we describe a straightforward approach to correct for these distortion artifacts, creating an alternative to previously reported ray-tracing schemes that are unable to apply these corrections in real-time. By implementing the proposed 3D recalibration algorithm on the graphics card of a standard computer, this feature can be applied in real-time. We validate the accuracy of the technique using OCT measurements of a highly curved object within a large imaging volume of 12.35 x 10.13 x 2.36 mm^3. The resulting 3D object shape measurements are compared against high-resolution and aberration-free optical profilometry measurements. Maintaining an optical resolution of <10 micron within the sample, both axially and transversally, we realized a real-time, high-resolution, large-volume OCT imaging system, capable of producing distortion corrected wide-field OCT data with a geometric surface shape accuracy of <15 micron.

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Sam Van der Jeught, Jan A. N. Buytaert, Adrian Bradu, Adrian Gh. Podoleanu, Joris J. J. Dirckx. 2012-12-07. Large-volume optical coherence tomography with real-time correction of geometric distortion artifacts. https://arxiv.org/abs/1212.1595

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