The Research On Information Reconstruction Of Spatially Modulated Snapshot Imaging Polarimeter

Polarization imaging technology is a new type of optical detection technology.The polarimeter that realizes this technology can not only acquire the light intensity information of the measured target,but also obtain the polarization information of the measured target and the background,which significantly increases the amount of information on the detected target scene.Spatially modulated snapshot imaging polarimetry can acquire all the Stokes parameters of the target through one measurement,which has wide application prospects in atmospheric remote sensing,target detection,astronomy,and biomedical diagnosis.This paper investigates the information reconstruction technology of spatially modulated snapshot imaging bias meter,and the main work is included as follows:Firstly,we derive the spatial modulation process of the snapshot imaging polarimetry.The theoretical derivation and analysis of the spatial modulation process of the snapshot imaging polarimeter using modified Savart polariscopes are presented,and the mathematical model of the system is constructed using the ray tracing method and the Jones matrix complex amplitude superposition method.And the realization process of reference ray method is analyzed.Secondly,we propose a information reconstruction method of spatially modulated snapshot imaging polarimetry based on coherent demodulation theory.The proposed reconstruction method is analyzed and discussed from three aspects: theoretical derivation,numerical simulation and experimental verification.The coherent demodulation algorithm is introduced from the signal processing field,and the reconstruction quality is evaluated by the difference and similarity of images in the simulation results.Based on obtaining the same reconstruction quality,the computation time of the traditional reference light calibration method and the coherent demodulation method are compared to verify the feasibility of the algorithm and improve the processing rate.The experimental system was set up in the laboratory,and the experimentally obtained target interference fringes were demodulated using the coherent demodulation reconstruction method,and the total experimental error was calculated.Lastly,we analyze the phase error and noise effect of spatially modulated snapshot imaging polarimetry.The phase delay amount error of the spatially modulated snapshot imaging polarimetry system are analyzed,and the theoretical model of the coherent demodulation method to extract the overall phase delay amount error is derived.The correlation coefficients and mean square error curves of different Stokes vector parameters under the influence of different signal-to-noise ratio were plotted.The robustness of information reconstruction method based on coherent demodulation is verified.Furthermore,the method can also be applied to the polarization imaging system of time-division or other spatially modulated snapshot imaging polarimetry systems with other different core modulation devices.It provides a novel method for the reconstruction of the information of the snapshot imaging polarimeter.