Reconstruction and calibration methods for a Mueller channeled spectropolarimeter.

Area of Science:

• Optical Engineering
• Spectropolarimetry
• Polarization Optics

Background:

• Channeled spectropolarimeters (CSP) measure spectrally resolved light polarization.
• Established methods exist for Stokes CSP, but Mueller CSP reconstruction and calibration are underdeveloped.
• Mueller matrix measurements are crucial for characterizing complex materials.

Purpose of the Study:

• To propose and validate novel methods for Mueller spectrum reconstruction.
• To develop and demonstrate calibration techniques for Mueller CSP.
• To enhance the practicality and applicability of Mueller CSP.

Main Methods:

• Mueller CSP modeled as a modulation matrix linking Mueller spectrum and spectrometer output.
• Optimization problem formulated for Mueller spectrum reconstruction using regularizer and residual threshold.
• In situ measurement of polarization states to construct a calibrated modulation matrix for Mueller CSP.

Main Results:

• Accurate, efficient, and noise-robust Mueller spectrum reconstruction achieved.
• Experimental calibration of both imaging and non-imaging Mueller CSP demonstrated.
• High accuracy in reconstruction shown with a root-mean-square error (RMSE) of 0.0371.

Conclusions:

• The proposed methods provide a practical solution for Mueller CSP reconstruction and calibration.
• These techniques integrate polarimetric and spectroscopic errors into a single calibrated matrix.
• The methods show potential for generalization to both imaging and non-imaging Stokes-Mueller CSP systems.