Influence of processing parameters on the scattering properties of fluorozirconate glasses prepared by the gas film levitation technique

Fluoride glasses for optical fibre applications were prepared using a containerless processing technique (the gas film levitation technique) to prevent the contamination of the glass melts by the crucible. Bulk glass samples of high optical quality were obtained by starting directly from a powder mixture of the different fluoride precursors. Differential scanning calorimetry, laser scanning tomography and light scattering measurements were used to measure the properties of the levitated glasses as compared to crucible-made glasses prepared in the same conditions. The bulk levitated glasses had an extended thermal stability range along with improved optical properties over the crucible-made glasses.