IR transmitting glasses in the YF3-PbF2-CdF2-AlF3 system

Glasses have been synthesised in the four component YF3-PbF2-CdF2-AlF3 system using conventional melt quench route. Several glasses have been prepared by varying YF3 and CdF2 content. Glasses exhibit up to 65-70% transmission and extended cutoff up to nearly 9.5 mu m. The glass transition temperature in these four component fluoride glasses ranged from 311 degrees C to 364 degrees C and the thermal stability index(T-x - T-g) was close to 113 degrees C for an optimised composition. Chemical durability studies in de-ionised water showed an excellent resistance to water attack. Excellent IR behavior, which compares well with ZrF4 and AlF3 based glasses, coupled with thermal and chemical stability, make these glasses promising for optical component design and fabrication. (C) 1998