Single-shot multispectral birefringence mapping by supercontinuum vector beams.

We demonstrated a single-shot, multispectral birefringence mapping by use of a supercontinuum (SC) vector beam. The vector beam, which was generated by a pair of axially symmetric wave plates, leads to angular-variant polarization modulation to divide birefringence properties of a sample substrate into Fourier space. This strategy allows multispectral birefringence mapping from a single-shot image captured by a multispectral imaging detector. For SC vector beam analysis, we also compensated the retardance error of the axially symmetric wave plate in the superbroadband spectrum. Resolutions of retardance and azimuthal angle were 0.4° and 0.2°, respectively, and the spatial resolution was 60 µm. Those results are expected to provide us a single-shot, multispectral birefringence mapping with high spatial resolution as compared with using a scanning laser microscope. Our proposal has extendibility to develop high-speed, high-resolution birefringence imaging spectroscopy.

Detection of birefringence singularity by supercontinuum vector beam.

We demonstrated detection of birefringence singularity on the space-variant retarder with an inhomogeneous birefringence distribution by supercontinuum vector beam. The birefringence measurement by supercontinuum vector beam analysis provides kinematics of a singularity point on the space-variant retarder. We conducted numerical calculations and experiments for proof of principle. The calculated results were characterized by relative positions with (x0,y0) between the singularity point and the vector beam. In the experiments, we measured the retardance and the azimuthal angle from intensity profile on a single-shot image captured at wavelengths of λ=450, 550, and 650 nm. The retardances at λ=450nm and 550 nm were changed from Δ=112∘ to 131° and from Δ=120∘ to 152° when the x0 displacement of the space-variant retarder moved from 0 to 350 µm. The measured retardance corresponded with the calculated results in the function of the position of birefringence singularity.

Extraction of polarization properties of the individual components of a layered system by using spectroscopic Mueller matrix analysis.

In semiconductor and optics fields, some devices are constructed with layered systems including two or three individual layers. Measurement of polarization properties of the individual components of these layered systems is often desired. In this paper, we present methods allowing the simultaneous extraction of the polarization parameters of the individual components by analyzing spectroscopic Mueller matrices (measured at two wavelengths). We have studied both retarder-retarder and retarder-polarizer-retarder systems. The validities of the methods were successfully tested using both simulations and real polarization systems.