Preparation and properties of InF3-GaF3-PbF2-ZnF2-CdF2-LaF3-HfF4 glasses

New fluoride glass compositions have been investigated The compositions wer e prepared by introducing cations into the basic ZnF2-InF3-GaF3-PbF2-LaF3 g lass system. Incorporation of cadmium strongly increases thermal stability. Addition of zirconium or hafnium improves the critical cooling rate of the se compositions The most stable glass composition against crystallisation w as determined to be 18InF(3). 20GaF(3). 3PbF(2). 10.5Zn(2). 10.5CdF(2). 4La F(3). 5HfF(4) (mol%). The InF3/GaF3 based glasses have a lower phonon energ y than ZBLAN glasses and are highly transparent in the longer wavelength re gion beyond 7 mu m. Additionally, a higher emission efficiency of a doped r are earth ion (Pr3+) in the InF3/GaF3 based glass was observed.