Partial polarization may be the result of a scattering process from a fully polarized incident beam. It is shown how the "loss of polarization" is connected with the nature of scatterers (surface roughness, bulk heterogeneity) and on the receiver solid angle. These effects are theoretically predicted and confirmed via multiscale polarization measurements in the speckle pattern of rough surfaces. "Full" polarization can be recovered when reducing the receiver aperture.

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Micrometer scale resolution full-field optical coherence tomography (FF-OCT) is developed for imaging human graft corneas. Three-dimensional (3-D) images with ultrahigh resolution (respectively, 1 and 1.5 μm in the axial and transverse directions), comparable to traditional histological sections, are obtained allowing the visualization of the cells and the precise structure of the different layers that compose the tissue. The sensitivity of our device enables imaging the entire thickness of the cornea, even in edematous corneas more than 800 μm thick. Furthermore, we provide tomographic 3-D images of laser incisions inside the tissue at various depths without slicing the studied corneas. The effects of laser ablations can be observed, along various optical sections, directly in the bulk of the sample with high accuracy, providing information on the interface quality and also imaging tiny changes of the tissue structure. FF-OCT appears to be a powerful tool for subcellular imaging of the corneal structure and pathologies on the entire thickness of the tissue as well as interface quality and changes in the collagen structure due to laser incisions on ex vivo human cornea.

An ellipsometric technique based on angle-resolved light scattering is addressed to open applications in the field of imaging in random media. The first experimental demonstration is given to prove the selective extinction of different scattering sources such as surface roughness and bulk heterogeneity in optical components and liquids. The results are compared with theory.

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