Experimental Characterization of Polarized Light Backscattering in Fog Environments.

Area of Science:

• Optics and Photonics
• Atmospheric Optics
• Polarimetry

Background:

• Fog significantly impacts light propagation and scattering, posing challenges for optical imaging systems.
• Polarization properties of light can carry crucial information about scattering media.
• Understanding light polarization behavior in fog is vital for developing robust imaging technologies.

Purpose of the Study:

• To experimentally characterize the polarization behavior of light backscattered through fog.
• To evaluate linear and circular polarization signals under controlled fog conditions.
• To investigate the impact of fog density on polarization signals and the polarization memory effect.

Main Methods:

• Utilized a polarimetric orthogonal state contrast imager and a polarized white illuminator.
• Conducted experiments in a macro-scale fog chamber with artificial fog.
• Analyzed backscattered linear and circular polarization signals as a function of meteorological visibility.

Main Results:

• Confirmed the polarization memory effect for circularly polarized light, indicating maintained helicity in backscattering.
• Identified the circular cross-polarized channel as the least susceptible to fog-induced backscattering.
• Demonstrated the persistence of polarization signals across varying fog densities.

Conclusions:

• Circularly polarized light exhibits a polarization memory effect when backscattered through fog.
• The circular cross-polarized channel is optimal for active polarimetric imaging in foggy environments.
• Results provide essential data for designing effective outdoor polarimetric imaging systems for use in fog.