Static dual-channel polarization imaging spectrometer for simultaneous acquisition of inphase and antiphase interference images

Abstract

The raw data acquired by Fourier-transform imaging spectrometers are the physical superposition of an interferogram and image. To reconstruct an accurate spectrum from a pure interferogram via Fourier transformation and get a pure image that is undisturbed by fringes, the interferogram and the image need to be separated. Although it can be achieved by digital image processing, heavy computations with approximation would be introduced. To overcome these drawbacks and in the meantime avoid the influence of the rapid changes of the observed scene and the perturbations of the rotating elements, a static dual-channel polarization imaging spectrometer that can simultaneously acquire inphase and antiphase interference images is presented. The extraction of a pure image and pure fringe can be simply achieved from the difference and the summation of the two interference images, respectively. The feasibility of the spectrometer and its features are described, and the influence of the polarization direction of the polarizers on the background image and fringe is discussed.

Compact and static Fourier transform imaging spectropolarimeters using birefringent elements

“…Recent progress in the Fourier transform imaging spectrometers that based on birefringent interferometers has remarkably enhanced the performance of static, compactness, and robustness, especially the capability to maintain polarization transmission accurately [21][22][23][24][25][26][27][28][29][30][31][32][33][34]. However, such spectrometers can only acquire a linerly polarized component due to the front fixed polarizer.…”

Efficient background removal based on two-dimensional notch filtering for polarization interference imaging spectrometers

“…However, the interpolation algorithm used in EMD needs heavy computation, which affects the speed of the algorithm [15] . Mu et al [16] proposed an optical assistant method to overcome the drawbacks of digital signal processing methods, but the limitation of their system is that all polarizers must be placed at ideal positions. In practical applications, digital image processing methods have better adaptability and can be applied to different PIISs more easily.…”