Procedural modification in making chalogenide glass and optical fibers has resulted in the reduction, and, in some cases, the elimination of water and hydrogen absorption bands. As a result of this new approach, transmission in the 2.5μm (4000 cm -1) to 7 μm (1428 cm-1) region is improved by dB loss of two orders of magnitude. The methods are as fol-lows: 1. Elimination of hydrogen sulfide absorption bands from As2S3 glass by selectively doping the glass with a fraction of ppm As203 to act as a hydrogen getter. 2. Elimination of water absorption bands from As2S3 glass by baking out the quartz ampoule at 900°C under high vacuum and by using vacuum-distilled elemental powdered sulfur as a starting material. Sulfur is known to be fairly hygroscopic, especially in the powdered form. Thus, it is a potential source of H2O contamination.
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