Compact spectral-polarization-modulation method for rapid and versatile polarization measurements in interferometric imaging

Polarization-based detection technologies have broad applications across various fields. Integrating polarization with interferometric imaging holds significant promise for simultaneously capturing three-dimensional structure and polarization information. However, existing interferometric polarization measurement methods often rely on complex setups and sacrifice the acquisition rate or axial imaging range for parameter diversity. In this study, we presented an efficient and compact interferometric polarization measurement method based on spectral-polarization-modulation (SPM) and integrated it with optical coherence tomography (OCT) to construct an advancing interferometric imaging system called SPM-OCT. This method can extract birefringent and dichroic parameters from the polarization-modulated signal without reducing the acquisition rate or the axial imaging range. Imaging experiments on standard polarization elements, biological tissues, and gold nanorod (GNR) phantoms demonstrated that our proposed method provided accurate birefringent and dichroic parameters and avoided phase jump errors. Especially, the dichroic parameters obtained from our system can distinguish GNRs from biological tissues with high contrast. Overall, the rapid and simple polarization measurement of the SPM method is expected to advance the interferometric imaging method and inspire new research directions in polarization measurement technology.