Brasselet is a CNRS researcher at Institut Fresnel developing polarization- and orientation-resolved fluorescence microscopy, using controlled excitation and detection polarization states to map the 3D orientation and organization of fluorescent probes and biomolecular assemblies (e.g. lipid order, amyloid and cytoskeletal structures) at and beyond the single-molecule level, including recent work on the mathematical foundations of polarimetric microscopy.