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Published on: September 5, 2019
Geodesic distance on non-singular coherency matrix space in polarization optics
1LAGIS-FRE CNRS 3303 Université Lille 1, Sciences et Technologies, Lille 59655, France. vincent.devlaminck@univ-lille1.fr
Summary
We introduce a geodesic distance for polarization analysis, improving imaging polarimetry. This new metric enhances clustering algorithms like K-means for better data interpretation.
Area of Science:
- Optics and Photonics
- Data Science
- Mathematical Physics
Background:
- Polarization analysis is crucial in imaging polarimetry.
- Current methods often use Euclidean distance, which may not be optimal for polarization data.
- Non-singular coherency matrices describe polarization states.
Purpose of the Study:
- To define and investigate a geodesic distance for the polarization space of non-singular coherency matrices.
- To compare the properties of this geodesic distance with the Euclidean distance for interpixel comparisons.
- To evaluate the performance of a geodesic K-means clustering algorithm in imaging polarimetry.
Main Methods:
- Definition of a geodesic distance on the manifold of Hermitian positive definite matrices (HPD(2)).
- Mathematical formulation of the distance and mean value in this metric space.
- Application of a geodesic K-means clustering algorithm to simulated and real polarimetric imaging data.
Main Results:
- The geodesic distance is directly related to the Jones calculus.
- The geodesic distance offers advantages over the Euclidean distance for interpixel comparisons in imaging polarimetry.
- The geodesic K-means algorithm demonstrates improved performance compared to classical methods.
Conclusions:
- The proposed geodesic distance provides a more appropriate metric for polarization space analysis.
- This approach enhances the accuracy and effectiveness of clustering algorithms in imaging polarimetry.
- The geodesic method offers a significant advancement for analyzing polarimetric data.
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