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Channeled modulation polarization imaging technology can obtain full polarization information of targets through a single frame of image, with advantages such as compact, low cost, and without electric rotating accessories. It has important application value in remote sensing, biomedical, national defense, and so on. The key point of channeled modulation polarization imaging technology is to modulate the four Stokes parameters that characterize polarization to different carried frequencies through amplitude modulation, and then use the frequency domain to separate the four two-dimensional Stokes parameters. Different channels are intercepted by a bandpass filter and subjected to inverse Fourier transform, which can achieve four two-dimensional distribution pictures of the Stokes parameters. Interference is the core of this technology, which is achieved through birefringent crystals or spectroscopic interferometers. After splitting, interference occurs in the focal plane, generating carrier frequency. However, a serious problem has been troubling researchers in this field, which is how to design birefringent crystals to achieve amplitude modulation of Stokes parameters. The amplitude of the interference fringes of the beams needs to be divided corresponds one-to-one with the Stokes parameter after interference. The current spectroscopic design mainly relies on experience and luck, lacking unified standards, which will affect the efficiency of system design. To solve this problem, relying on the representation of the electric field vector of light, the mathematical expression of Stokes parameters and the corresponding relationship with the spectral results are analyzed in reverse. Then, based on the physical meaning of Stokes parameters, phase modulation is used to achieve the representation of certain parameters for the sum of light intensities and the representation of certain parameters for the difference in light intensities. Ultimately, a correspondence is formed between different spectroscopic results and the detected polarization parameters and proposed modulation criteria for channeled modulation by linking the physical meaning and mathematical model of Stokes parameters. On the one hand, this study is beneficial for the targeted design of channeled modulation polarization imaging technology in different application scenarios for different parameter detection requirements, and on the other hand, it can guide the design of optical systems for different spectral requirements in birefringent crystal design, making the design of this technology more standardized.
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