Mueller-Gabor holographic microscopy

Despite the emergence of various methods for Mueller matrix recovery, achieving complete volumetric Mueller matrix retrieval remains a challenge. An alternative approach that leverages in-line Gabor holography to comprehensively extract polarization information from volumetric samples is introduced in this context. The proposed polarization-sensitive in-line Gabor holographic setup enables the recovery of the complete Mueller matrix of three-dimensional (3D) samples after the numerical repropagation of the holographically rendered complex field to various sample planes. This proposal is validated using a calibrated birefringent polarization test target, a sample of Calcium Oxalate crystals, and a volumetric sample containing microplastics, providing the 3D measurement of polarimetric parameters such as diattenuation, polarizance, depolarization, and retardance. The results agree with those obtained through reference methods based on image-plane brightfield polarimetry. The in-line Gabor holographic system proposed is sensitive to the axial variations in polarimetric information within volumetric samples without any mechanical movement nor optical adjustments— an accomplishment that remains elusive to conventional image-plane reference methods and non-holographic/interferometric systems. These findings emphasize the versatility and potential of this alternative approach in recovering the intricate polarization characteristics of 3D specimens, offering the first in-line holographic Mueller imaging to the best of the authors' knowledge.