Figure 3. Scanning electron microscopy images of polydisperse nanostructured (upper left) and monodisperse latex (upper right) particles. Example of a hyperspectral (H) polarized BRDF for such media (bottom). λ: Wavelength.
To complement these measurements, 5 we developed numerical tools based on stochastic or radiative transfer approaches. We simulated light scattering in various media—from dense suspensions to coatings—as detected by sensors taking into account the experimental protocol. Then, we compared these results with our own experimental data to determine the value of an objective function. This function is minimized by an iterative process, modifying numerical inputs such as the particle size distribution, the geometry, the concentration, and the optical index of scattering.
Our new instrument is dedicated to measuring the hyperspectral polarized angular signature of various materials, from liquid to solid samples. Measurements are carried out on bulk materials in addition to nanomaterials. We consider the hyperspectral polarized BRDF a powerful new way to study the optical properties of nanomaterials.
ls in our numerical models to reduce the error in determining a nanoparticle's optical properties. We are currently evaluating new materials to measure and simulate unexpected optical properties at the nanoscale.
Part of this work was supported by the Région Midi-Pyrénées. The authors wish to thank M.-L. de Solan from the Chemical Engineering Laboratory of Toulouse for helpful discussions and contributions.
