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Updated: Jul 7, 2026
12:28
Imaging Plasma Membrane Deformations With pTIRFM
Published on: April 2, 2014
Summary
High-resolution skylight polarization maps reveal that neutral points are broader than expected. These findings, measured near sunset, are explained by a multiple-scattering model.
Area of Science:
- Atmospheric optics
- Polarimetry
Background:
- Skylight polarization patterns are influenced by atmospheric conditions.
- Neutral points in skylight polarization have been historically observed.
Purpose of the Study:
- To create high-resolution maps of skylight polarization.
- To investigate the characteristics of neutral points near sunset.
- To analyze polarization data from inland and coastal sites.
Main Methods:
- Acquisition of digital images of clear skies using a linear polarizing filter.
- Measurement of polarization (P) and normalized Stokes parameter (Q).
- Analysis of polarization data near sunset at multiple locations.
Main Results:
- High-resolution maps of skylight polarization were generated.
- Neutral points (Arago and Babinet) were observed to be part of larger areas with near-zero polarization.
- Consistent patterns were found across different sites, including coastal and inland locations.
Conclusions:
- The extent of neutral points in skylight polarization is larger than previously understood.
- A multiple-scattering model provides a partial explanation for observed polarization patterns.
- Further research may refine atmospheric models based on these findings.
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