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Spatially modulated full-polarization imaging systems can obtain full Stokes parameter information by single imaging, with strong characteristics of real-time execution and stability. Since all the polarization information is modulated into an interferogram, demodulation becomes an essential step. As the resolution of the obtained image continuously increases, the data to be calculated also increase. Therefore, a higher speed for the demodulation process is requisite. This article proposes a local filtering method and bypasses the frequency centralization method in the frequency domain to improve the speed of demodulation. The demodulation time of an interferogram of size 1024×1024 pixels was reduced from 3.027 473 s to 0.134 637 s, increasing the speed of demodulation by 97.72%. Meanwhile, the demodulation time of an interferogram of size 6144×6144 pixels was reduced from 444.329 92 s to 4.637 069 s, increasing the speed of demodulation by 98.75%.

Spatially modulated full polarization imaging is the method of modulating the polarization information of a target into a single interferogram, which has a good real-time feature. Since polarization modulation lenses are made of birefringent crystals, they will produce chromatic dispersion. Therefore, the interference fringes on the interferogram will become blurred, affecting the subsequent demodulation processing. It is necessary to determine the bandwidth limit of the incident light. Based on these considerations, this paper analyses the distribution of the polarization information in the frequency domain and proposes a method of determining the bandwidth limit based on the pixel size in the frequency domain.

Based on semiclassical theory, a model of the interaction between neutral atoms and the laser standing wave field has been established in this article. The trajectories and the deposition characteristics are analyzed with channel effect, and the full width at half maximum of nano-grating is 96.70, 0.532 and 12.16 nm when the divergence angle, spherical and chromatic aberration are discussed, respectively. The simulation results show that the contrast of the stripes decreases with the increasing divergence angle of the atomic beam. Also, the contrasts of the stripe are 85.2:1 and 5.33:1 when the divergence angles equal 0.1 and 0.3 mrad. Owing to the scission of the stripe, the quality of the deposition deteriorates with a divergence angle over 0.5 mrad.