Abstract: The invention concerns monomode or multimode optical fibers provided with a lens with an end taper, obtained by selective photopolymerization of a formulation, and with improved performances through the use of novel parameters and technical processes enabling production of polymer tapers with optimized characteristic required for a wide range of applications. The monomode or multimode optical fibers can, for certain specific applications, be equipped with a metallized polymer taper except for a nanometric opening for sensing or emitting light or a polymer taper whereof the formulation contains fluorescent particles. The novel fibers are essential components in various fields such as telecommunications (high performance connectors) or instrumentation (optical radiation comparator probes for scanning optical microscopy and near-field optical microscopy).

Abstract: The invention concerns monomode or multimode optical fibers provided with a lens with an end taper, obtained by selective photopolymerization of a formulation, and with improved performances through the use of novel parameters and technical processes enabling production of polymer tapers with optimized characteristic required for a wide range of applications. The monomode or multimode optical fibers can, for certain specific applications, be equipped with a metallized polymer taper except for a nanometric opening for sensing or emitting light or a polymer taper whereof the formulation contains fluorescent particles. The novel fibers are essential components in various fields such as telecommunications (high performance connectors) or instrumentation (optical radiation comparator probes for scanning optical microscopy and near-field optical microscopy).

Abstract: Process for obtaining a transparent article with a refractive index gradient, including the steps of: (1) irradiating a crosslinkable liquid mixture of base photopolymerizable monomers which is modulated spatially in intensity and/or irradiation time to form a structure gradient according to a desired index profile until a self-supporting polymer matrix is obtained; (2) swelling the polymer matrix to thermodynamic equilibrium in a swelling composition containing a polymerization initiator and one or several polymerizable monomers producing a polymer of different refractive index from the refractive index of the matrix obtained in step (1); and (3) polymerizing the swelling composition which has diffused into the matrix homogeneously, thereby obtaining a transparent article with a refractive index gradient.