Backscattering Mueller matrix measurement scheme using the same polarizing–analyzing optics

Mueller matrix measurements are most commonly performed using a set of polarization state generating (PSG) optics and an independent set of polarization state analyzing (PSA) optics. However, for polarized confocal microscopy and polarization sensitive optical coherence tomography it would be advantageous if the same set of polarization optics could be used for both PSG as well as PSA. This has not been possible because, in this configuration, a complete set of incident and analyzer states cannot be generated using polarizers and waveplates alone. In an earlier attempt to address this issue it was shown that by using two Faraday rotators, with independently variable circular retardance, in the polarization optics, complete Mueller matrix measurement can be performed. However, a practical implementation of this approach has proved to be difficult due to the requirement to vary the circular retardance. In this paper we show that by incorporating only one Faraday rotator in the polarization optics, one can generate the complete set of incident and analyzer states required for Mueller matrix measurements without the need to vary the circular retardance of the Faraday rotator.