OPTICAL-PROPERTIES AT HIGH-TEMPERATURE OF MOLTEN SODA-LIME-SILICA GLASSES CONTAINING IRON-OXIDE

High temperature laser spectrometry has allowed to measure transmittiv ity and reflectivity of high temperature liquids up to 1 500-degrees-C in non contamination conditions. An elaborate study was made in the c ase of glasses containing iron oxide. Results are reported for differe nt iron concentration and redox ratio. The influence of composition an d temperature on spectral absorption was investigated and phenomenolog ical relationships were established for certain conditions. The interp retations proposed allow to explain and to predict in some extent the variation of absorption with temperature, both the exponential variati on at short wavelength and the shift towards the I.R. of the d-d bands .