Design and realization of a spectroscopic optical coherence tomography system for medical applications

In this manuscript, we present the design and realization of a Fourier-Domain Spectroscopic-OCT system with a simple spectrometer, based on off-the-shelf parts and a low-cost, state-of-the-art broadband S-LED light source with three spectrally shifted S-LED modules. Depth resolved spectral absorption measurements in the wavelength range from 750 nm to 850 nm are demonstrated using an expansion of OCT called spectroscopic OCT (SOCT). The realized setup was tested and evaluated towards its ability to measure physical parameters such as blood oxygen saturation quantitatively in vivo. Different sample configurations including multilayer setups and scattering layers were used. Additionally, we present the theoretical model and experimental verification of interferences between autocorrelation terms and the signal carrying crosscorrelation terms, strongly affecting the absorption measurements. A simple background subtraction, minimizing the artifacts caused by the interferences of autocorrelation and crosscorrelation terms is presented and verified.