Subwavelength metrological chracterization by Mueller matrix polarimeter and finite difference time domain method

•Polarimetric response of wire grid polarizer (WGP).•Subwavelength metrological characterization basically for periodic structure.•Mueller matrix polarimeter and finite difference time domain approach for subwavelength structures.•Non-destructive rapid measurement of material on real time.•Best matching of the measured values and convergence with high accuracy and precision.

Wire grid polarizers (WGP), are sub-wavelength gratings with applications in display projection system due to their compact size, wide field of view and long-term stability. Measurement and testing of these structures are important to optimize their use. This is done by first measuring the Mueller matrix of the WGP using a Mueller matrix polarimeter. Next the finite difference time domain (FDTD) method is used to simulate a similar Mueller matrix thus providing the period and step height of the WGP. This approach may lead to more generic determination of sub-wavelength structures including diffractive optical structures.