Optimization of SNR, sensitivity values by evaluating the relative spacing between the partial mirror and scanning reference mirror for multiple reference optical coherence tomography

Multiple reference optical coherence tomography (MR-OCT) is a time-domain interferometric imaging platform which promises to be realized as a low cost, compact imaging technology. The optical configuration of MR-OCT makes use of multiple reflections between a partial mirror and the axially scanning reference mirror to enhance the axial imaging depth compared to the otherwise shallow scanning range of the voice coil or piezo actuator. Since each reflection on the partial mirror causes an optical path delay, the focusing of each higher order of reflection is changing. That means the beam diameter, beam collimation and therefore the interference visibility are changing as well. This investigation focuses on how the spacing between the partial mirror and the scanning mirror affects the system’s sensitivity and SNR values. The potential to improve the sensitivity of higher orders of reflections related to deeper regions in a sample will be studied.