Descriptif
The course presents the physical foundations of light propagation in disordered scattering media (such as paints, powders, colloidal suspensions, cold atomic clouds or biological tissues) and introduces imaging techniques using measurements of diffuse light (average intensity) or speckle (intensity fluctuations). The main theme of the course is scattering and diffusion of light, but the generality of the concepts and methods allows direct links to other topics in wave physics, including acoustics or electronic and matter waves.
The study wave in complex media, at the interface between innovative applications and fundamental physics, is nowadays a very active field of research.
Objectifs pédagogiques
On completion of the course students should be able to:
At the end of the course, students will be able to:
Analyze scattering regimes and identify the appropriate model to describe a given problem.
Describe and predict the main features of the light scattered from complex (disordered) media
Apply methods to solve simple problems and calculate orders of magnitude.
Interpret an observation and quantitatively analyze a measurement in a real case.
Outline a system for optical detection or imaging through (or in) a highly scattering medium.
Diplôme(s) concerné(s)
Parcours de rattachement
Pour les étudiants du diplôme Diplôme d'ingénieur de l'Institut d'Optique Théorique et Appliquée
Wave propagation, physical optics, basic knowledge in statistical physics
Format des notes
Numérique sur 20Littérale/grade réduitPour les étudiants du diplôme Diplôme d'ingénieur de l'Institut d'Optique Théorique et Appliquée
Vos modalités d'acquisition :
Examen oral
Le rattrapage est autorisé (Note de rattrapage conservée écrêtée à une note seuil de 12)- Crédits ECTS acquis : 1.5 ECTS
Le coefficient de l'UE est : 1.5
La note obtenue rentre dans le calcul de votre GPA.
Programme détaillé
Syllabus
Light scattering by particles
- Scattering amplitude, cross sections
- Examples (Rayleigh, Rayleigh-Gans and Mie scattering)
Multiple scattering of light in disordered media
- Statistical description. Ballistic and diffuse intensity
- Radiative transfer equation and diffusion approximation
- Applications : sensing and imaging using the average intensity
Speckle
- Intensity statistics in laser speckle produced by a phase screen (single scattering)
- Speckle produced by a strongly scattering layer (diffusive regime)
- Applications to sensing and imaging
- Controlling speckles : wavefront shaping
Introduction to more advanced topics
- Optics of partially ordered materials
- Coherent backscattering and localization
Textbooks/bibliography:
Carminati and J.C. Schotland, Principles of Scattering and Transport of Light (Cambridge University Press, 2021)
J.W Goodman, Statistical Optics (Wiley, 2000)
J.W Goodman, Speckle Phenomena in Optics (Freeman, 2010)
E. Akkermans and G. Montambaux, Mesoscopic Physics of Electrons and Photons (Cambridge University Press, 2007)
