Abstract
Since its first creation, glass has always fascinated with its optical properties, its ability to let light through without being invisible. One of the most spectacular achievements of optical glass is the optical fiber for which considerable work has been done to make it as transparent as possible. However, for twenty years, contrary to this quest for transparency, nanoparticles have been inserted into optical fibres. First designed to develop new lasers and amplifiers, the lowest possible particle-induced light scattering then sought has for the last four years, on the contrary, been exacerbated in order to develop new sensors.