Depth-sensitive instrument for Mueller matrix imaging measurements

We present an optical imaging approach that combines Spatial Frequency Domain Imaging (SFDI) and Mueller Matrix Imaging (MMI) to enable depth-resolved characterization of polarization properties in turbid media. By simultaneously exploiting the spatial selectivity of SFDI and the sensitivity of Mueller polarimetry to microstructural anisotropy, our method provides complementary contrast mechanisms that reflect both the layered structure and polarization-dependent behaviour of complex samples. Spatially modulated illumination at multiple frequencies is used to control the sampling depth, while full Mueller matrix measurements are performed at each frequency to capture the evolution of polarization as a function of depth. Experimental results in phantoms and biological tissue demonstrate the potential of this dual-mode technique to distinguish subsurface polarization features that would otherwise remain obscured in conventional imaging. This integrated approach opens new possibilities for applications requiring non-invasive, depth-sensitive analysis of anisotropic or scattering structures, such as biomedical diagnostics or material characterization. • Combines SFDI and Mueller matrix for depth-sensitive polarization imaging. • Enables separation of superficial and deep polarization signals in turbid media. • Structured light at multiple frequencies controls probing depth precisely. • System validated on phantoms and tissues showing depth-resolved contrast.