Experimental study on atmospheric polarization characteristics measurement with different observation angles and wavelengths

Considering the potential application demands of atmospheric polarization effects in fields such as navigation, remote sensing, and astronomical observations, experimental research has been conducted to investigate the variations of sky polarization degree under different scattering angles and wavelength conditions. The ideal analysis models of atmospheric polarization characteristics have been established based on the Rayleigh scattering theory. The distribution features of polarization degree and polarization angle in the sky were investigated, and their varying laws with the scattering angle were provided by the simulation study. An experimental system for measuring the atmospheric polarization characteristics was constructed using a turntable, division of focal plane (DoFP) polarization camera, telephoto lens, and bandpass filters. The atmospheric polarization patterns were measured and studied at different observing angles and wavelengths. The experimental results indicate that the magnitude of sky polarization degree is closely related to the scattering angle and it reaches its maximum near 90°. At the four experimental measurement wavelengths of 500 nm, 700 nm, 870 nm, and 1065 nm, the measured values of the sky polarization degree were 0.75, 0.64, 0.41, and 0.28, respectively. The sky polarization degree exhibits a downward trend with the increase of wavelength, and the atmospheric polarization effect gradually weakens with the increase of wavelength. These conclusions provide a meaningful reference for selecting appropriate observation angles and wavelength ranges in astronomical observation and remote sensing applications.