Versatile Full-Field Optical Coherence Tomography with Adjustable Transmission-to-Reflection Ratio and Enhanced Signal-to-Noise Ratio

Abstract: Traditional full-field optical coherence tomography (FF-OCT) is effective for rapid cross-sectional imaging but often suffers from incoherent signals due to imbalanced light intensities between the sample and reference arms. While the high-throughput dark-field (HTDF) FF-OCT technique employs an asymmetric beamsplitter (BS) to achieve an asymmetric beam-splitting ratio and optimize the utilization of available light, the fixed beam-splitting ratio in the optical system limits HTDF FF-OCT to effectively measuring only specific types of samples with certain scattering intensities. To address this limitation, we propose a more versatile FF-OCT system with an adjustable transmission-to-reflection ratio. This system enables accurate measurement across a broader range of samples by optimizing the light source and finely tuning the polarization to achieve the ideal ratio for different materials. We also observed that both signal-to-noise ratio (SNR) and imaging depth are influenced by the beam-splitting ratio. By precisely adjusting the beam-splitting ratio, both SNR and imaging depth can be optimized to achieve their optimal values.