Snapshot full-Stokes imaging spectropolarimetry based on division-of-aperture polarimetry and integral-field spectroscopy

摘要

Snapshot imaging spectropolarimetry is emerging as a powerful tool for mapping the spectral dependent state of polarization across most of scenarios (stable and variable), owing to its capability of real-time parallel acquisition. In this paper, two schema of snapshot full-Stokes imaging polarimeters (SFSIP) based on division-of-aperture polarimetry are presented firstly. In compliance with the definition of Stokes parameters, the first SFSIP consists of three Wollaston prisms with superior extinction ratio and simultaneously measures six polarimetric intensities (I_0, I_(90), I_(45), I_(135), I_L and I_R) of scene. However, the spatial resolution of each polarimetric image only occupy one-six of detector. To increase the spatial resolution, the second SFSIP comprises a optimal four-quadrant polarization array and a pyramid prism is used to simultaneously acquire four polarimetric intensities. Since the optimal four-quadrant polarization array consists of a uniform linear polarizer and four 132° retarders with different azimuth of fast axis, the signal-to-noise ratio for each of the recovered Stokes parameters will be balanced and enhanced. Finally, the four-quadrant polarization array and pyramid prism are integrated into a integral field spectroscopy to construct a snapshot full-Stokes imaging spectropolarimetry (SFSISP). It is used to map the spectral dependent full Stokes parameters across a scene in real time.