Computational 3D resolution enhancement for optical coherence tomography with a narrowband visible light source

Abstract

Phase-preserving spectral estimation optical coherence tomography (SE-OCT) enables combining axial resolution improvement with computational depth of field (DOF) extension. We combine SE-OCT with interferometric synthetic aperture microscopy (ISAM) and computational adaptive optics (CAO) to obtain a high 3D resolution over a large depth range with a narrow bandwidth visible light super-luminescent diode (SLD). SE-OCT gives up to five times axial resolution improvement from 8 μm to 1.5 μm. The combination with ISAM gives a sub-micron lateral resolution over a 400 micrometer axial range, 16 times the conventional depth of field. CAO removes residual aberrations, resulting in high quality images. The results show that phase-preserving SE-OCT is sufficiently accurate for coherent post-processing, enabling the use of cost-effective SLDs in the visible light range for high spatial resolution OCT.