Polarization-Resolved Digital Holographic Sensing for Simultaneous Morphological and Polarimetric Characterization of...

Multiparameter optical sensing of micrometer-sized particles requires morphological and optical responses to be resolved for the same particles. We present a polarization-resolved digital holographic (PRDH) system combining digital in-line holography with division-of-focal-plane polarimetry. Numerical refocusing associates the three-dimensional location of each resolved particle with its equivalent diameter, major and minor axes, perimeter, projected area, and shape factor, together with the linear Stokes parameters S₀, S₁, and S₂ and the degree of linear polarization (DoLP). For three standard glass-microsphere groups, the average absolute relative deviation between group-mean measured diameters and the nominal reference values was approximately 5.5%. The 5 and 10 micrometer borosilicate groups had mean DoLP values of 0.849 and 0.843, respectively, while other sample groups exhibited different responses. An exploratory regression against the adopted nominal refractive-index values is reported as a conditional group-level description, not as a refractive-index calibration. T-matrix calculations at 520 nm illustrate angular variations with size and refractive index without quantitatively reproducing the complete holographic measurement. Ice-cloud-chamber measurements further demonstrate the application of the particle-resolved analysis. PRDH thus provides associated positional, projected morphological, and linear-polarization information within a three-dimensional particle field.