A collinear reflection Mueller matrix microscope for backscattering Mueller matrix imaging

This is the authors' abstract. We don't add key points for this paper.

We developed a collinear reflection Mueller matrix microscope by adding polarization state generator (PSG) and polarization state analyzer (PSA) into the illumination and detection optical paths of a commercial metallurgical microscope. It is found that specific efforts have to be made to reduce the artifacts due to the intrinsic polarizations of the optical system, particularly the dichroism due to the 45° beam splitter. We adopt a new calibration method based on numerical reconstruction of the instrument matrix to minimize the artifacts of the beam splitter. Using a reflection mirror as the sample, maximum error in the calibrated Mueller matrix elements is smaller than 0.02. Preliminary test results using electrospinning samples show that the collinear reflection Mueller matrix microscope can effectively minimize the dependence of Mueller matrix to azimuth orientations and enhance the capability for characterizing the microstructural features of anisotropic samples.