Coded aperture full-stokes imaging spectropolarimeter

Abstract

A coded aperture full-Stokes imaging spectropolarimeter (CAFIS) based on a combination of coded aperture spectral imager and polarization spectrum modulation is demonstrated. The CAFIS uses a rotatable retarder and a rotatable polarizer as polarization spectrum modulation components to modulate the polarization information on the spectrum first, then the CAFIS achieves aperture coding with a digital micromirror device (DMD). After passing through a dispersive element, the coded polarization modulated spectral images are recorded by a CCD camera. The polarization modulated spectral images with the camera’s intrinsic spatial resolution are estimated with sparsity-constrained optimization from the acquired images, and the full-Stokes spectral images are computed by the demodulation algorithm. The principle and feasibility are verified via simulations. The relationship between the configuration of polarization spectrum modulation components and the reconstruction quality is investigated in this paper as well.