Research On Polarized Pixel Response Modeling For Division Of Focal Plane Polarimeter

Polarization of light is another important property in addition to intensity,spectrum and phase.The generation mechanism of polarization characteristics is the physical information resulting from the “asymmetry” of processes such as reflection,refraction,absorption,and scattering.Polarized images try to obtain the vector nature of light from real scenes.Polarization imaging is the process of recording the polarization state of the light in the scene.It provides valuable information that cannot be obtained directly from other characteristics of the object.It can also capture polarization scene information that is difficult to express by other imaging methods.First,this paper introduces the application background and research status of polarization imaging technology in detail.It mainly includes the application value of polarization imaging in real life and the application status of polarization technology in various fields.The development history of polarization imaging technology is introduced in turn.Based on the theoretical basis of polarization imaging technology,the characteristics and principles of the division of focal plane(DoFP)polarization imaging system are analyzed.The core of the construction of DoFP polarimeter mainly includes micro-polarizer array.The response characteristics of polarized pixels are directly affected by the inherent defects of DoFP polarimeter.Accordingly,the response characteristics of polarized pixels are critical to correcting inherent defects.However,there are few reports on the response characteristics of polarized pixels.Therefore,this paper proposes a polarized pixel response model for DoFP polarimeter.The response model combines the response characteristics of traditional photoelectric imagers and micro-polarizer arrays.The proposed model includes six input parameters.They are major polarization responsivity,minor polarization responsivity,polarization orientation,exposure time,conversion gain,and gamma correction.Then,the polarization images captured at four linear polarization angles(0 °,45 °,90 °,135 °)by the Division of Time(Do T)polarization imaging system.The DoFP polarization images can be simulated.In general,we will obtain DoFP polarization images under ideal conditions,without considering the manufacturing error of the DoFP polarimeter.Therefore,this paper proposes a method for obtaining DoFP polarization images containing actual errors,based on the consideration of two polarization performance parameters,polarization angle and extinction ratio errors.The principle of this method is to calculate the polarization information through the calibrated polarization performance parameters and the measured Stokes vector.Finally,this paper builds a verification experiment system of the polarized pixel response model for the DoFP polarimeter,and calibrates the polarization performance parameters.The polarization pixel response model constructed by root-mean-square errors(RMSEs)of the model calculation results and actual measurement results was evaluated.The compared results under different artificial parameters show that the average root-mean-square-errors of each experimental data is less than one gray value,which proves the validity of the proposed model.At the same time,a Do T polarization imaging system was constructed to obtain intensity images at four linear polarization angles(0°,45°,90°,135°).Based on the calibrated polarization performance parameters and the calculated Stokes vector,the DoFP polarization image was simulated.The mean structural similarity(MSSIM)is used to compare the simulation results of DoFP polarization images under ideal conditions and actual conditions.