New fluoroindate glass compositions

Abstract

The limits of glass formation of new fluoroindate glass compositions have been determined for the basic systems InF3-BaF2-GdF3-20ZnF2-20SrF2-2XFn where X = Na, La and InF3-BaF2-2OZnF2-20SrF2-2GdF3-XFn where X = Ca and Y. The incorporation of small amounts of GaF3 and/or GdF3 increases strongly the thermal glass stability. All the fluoroindate compositions studied are highly transparent in the mid-infrared range; their transmission edge is shifted beyond 7 mum and the theoretical attenuation coefficient, extrapolated at the CO laser wavelength emission, is typically alpha = 100 dB/km. Large bulks and preforms have been prepared allowing the drawing of optical fibers.