MultiScale transition of the scattered light polarization regimes – TraMEL
TRAMEL
Gradual Transition between Extreme States of Light Polarization
relationship between disorderd media and polarization
TRAMEL (Multiscale Transition of the Scattered Light Polarization Regimes) is devoted to the study of light depolarization in disordered media. Exact electromagnetic theories are coupled with statistical optics in order to rely the polarization degree of light to the microstructure of the scattering centers (roughnesses, bulk inhomogeneities…). A multiscale approach is introduced to take into account additional effects such as spatial depolarization. Polarization should be controlled in each speckle grain at propagation, hence allowing to reach predetermined targets. The gradual transition of polarization between two extreme regimes is predicted and measured. Repolarization of light by complex media is addressed. All studies are extended to a quantitative investigation of coherence. New signatures are emphasized and calibrated for a better probing of random media. Applications concern imaging and microscopy, biophotonics and medical, security…
Statistical optics, Electromagnetic Optics
Purchase order for facilities, recruitment of a PhD
Those submitted in the proposal
nothing at this step
Light depolarization is the key limitation of most optical techniques involving polarized interferences (microscopy, ellipsometry, imaging in random media…). Recently we built a concept to describe the progressive transition of light between the extreme regimes of "total polarization" and "total depolarization". This work is based on a multiscale investigation of light depolarization in a spatial average process, strongly connected with the experimental conditions (angular aperture, line width) and the scattering samples (surface roughness, bulk heterogeneities, scattering centers...). In this project we plan to predict and quantify the transition of light between these extreme regimes of polarization (total => partial => zero), on the basis of an hybridation between the formalisms of electromagnetic optics and statistical optics. Such prediction must be associated to the microstructure of the scattreing centers, in order to reveal at which scale full polarized interferences can be recovered. All results are applied to selective imaging in random media, where several signals (ex. surfaces) can be cancelled to the profit of others (ex. bulks), and where a buried object can be revealed in the presence of an optical key. Sophisticated modelization and metrology are involved in the project, for which reason we gathered 4 teams of Fresnel institute (Metrology, Imaging systems, Integral method, Finite elements), one from ONERA (statistical optics) and one from LATP (mathematics). This project would give a new strength to optical techniques based on polarized interferences, mainly in the extreme situations of high scattering regimes. To our knowledge all results (concepts, metrology and modelization) are entirerely original in this project. Applications concern imaging systems, communication and security, transportation...
Project coordination
Claude AMRA (CNRS - DELEGATION REGIONALE PROVENCE ET CORSE)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
Partnership
MAP2 CNRS - DELEGATION REGIONALE PROVENCE ET CORSE
SEMO CNRS - DELEGATION REGIONALE PROVENCE ET CORSE
DOTA ONERA - CENTRE D'ETUDES ET DE RECHERCHES DE TOULOUSE
RCMO CNRS - DELEGATION REGIONALE PROVENCE ET CORSE
HIPE CNRS - DELEGATION REGIONALE PROVENCE ET CORSE
LATP CNRS - DELEGATION REGIONALE PROVENCE ET CORSE
Help of the ANR 546,343 euros
Beginning and duration of the scientific project:
- 48 Months
