The sunlight reflected from object surfaces is partly polarized, which is the useful information for polarized remote sensing. Therefore, it is important to perform the field polarization measurement, which can not only obtain the true physical polarization characteristics of object, but also be used to match with the polarimetric measured results from the airborne observation. However, there is no research concern the difference of polarized reflectance property between natural background and manmade objects in the natural environment. In this paper, we measure Visible-Near Infrared spectral polarized reflectance properties of two natural surfaces (soil and grass) and six manmade objects (cement and five painted materials) over the hemisphere directions in the field. The measurements are carried out with an automatic polarimetric spectrometer equipped with the goniometer. The results indicate that the polarization reflectance of manmade objects and natural background show the obvious anisotropic characteristics. The soil and grass produce the maximum reflectance value in the backscattering direction, which is opposite to the manmade objects. The polarized reflectance factor of manmade object is much greater than natural background, which can be used to effectively distinguish the object and the natural background. Our study has a great potential for target detection and identification in the field.
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