Dual reference arm low-coherence interferometer-based reflectometer for optical coherence tomography (OCT) application

Abstract

The paper reports initial experimentation with an optical low-coherence reflectometer with two linked reference arms for optical coherence tomography (OCT) application. The reflectometer supports: (1) inherent doubling of achievable axial scanning range and, (2) quasi-simultaneous or simultaneous multiple specimen delay scanning. Extended axial scanning range was achieved simply by arranging the two reference arms, linked by a single variable optical delay line (ODL) for adjusting paths lengths, in opposite orientation to each other. This feature is particularly useful with ODLs of limited axial scanning range. The opposing reference arms scan different axial locations in the specimen remotely and quasi-simultaneous or simultaneous OCT imaging through multiple specimen delay scanning is possible. In this initial study the functionality of the dual channel reflectometer is illustrated by acquiring OCT images pairs at two axial positions quasi-simultaneously. The potential of the configuration in shortening A-scan time by factor 0.5 through simultaneous specimen multiple delay scanning is also explored in the paper.