An experimental procedure for quantitative evaluation of spectral resolution of spectrometer-based spectral domain optical coherence tomography

Optical coherence tomography (OCT) is an emerging optical technology that is capable of non-invasive cross-sectional imaging of biological tissues at high-speed, highresolution, and high sensitivity. OCT has been proven to be a potential tool for medical diagnostics and biomedical researches. One important parameter that governs an imaging depth of spectrometer-based spectral domain OCT (SD-OCT) is the spectral resolution of a spectrometer used in the system. Here, we have developed a laboratory procedure to evaluate the spectral resolution of a spectrometer during its alignment process. We have implemented the procedure to our custom developed spectrometer to improve its effective spectral resolution and hence the imaging depth of the SD-OCT system. The optimized spectral resolution of the spectrometer is necessary for extending an imaging depth of SD-OCT, which would be useful for many medical diagnostics, such as skin imaging and retina imaging.