从玻璃组分与玻璃光学折射率分布及零色散波长位置的影响机理出发, 研究低色散卤化物对硫系玻璃的色散调控作用.制备了Ge-Ga-Se-CsI硫卤玻璃, 利用差示扫描量热仪、红外椭偏仪、红外光谱仪等测试了该玻璃的物化性质, 分析了原料和玻璃提纯工艺、CsI含量对玻璃形成以及透过范围的影响, 并计算了该玻璃的材料色散.实验结果表明: 该玻璃的透过范围可覆盖可见光至中远红外波段(0.55~18 μm); 该玻璃的材料零色散点随着CsI含量的增加明显蓝移, 摩尔百分比为20%和40%的CsI含量可使该玻璃材料的零色散波长蓝移至3.5 μm和1.5 μm附近, 且该玻璃的热稳定性较好, 有利于低色散中红外光纤的制备和应用.结合玻璃提纯技术和高温聚合物保护拉丝光纤拉丝工艺, 获得了最低损耗为8.2 dB/m的单折射率硫卤玻璃光纤.

The dispersion functioning mechanism of low-dispersion halides on chalcogenide glasses is studied on the influence of glass composition optimizing, refractive index adjusting and zero-dispersion wavelength shifting, with the help of Ge-Ga-Se-CsI chalcohalide glass preparation. The physical and infrared optical properties of the glasses were tested by differential scanning calorimetry, infrared ellipsometer and infrared spectrometer. The purification process and glass composition to the glass formation and their optical properties were studied detailedly. The material dispersion curves of the two glass samples were calculated based on the measured data of refractive index. The experimental results show that the transmission range of the glasses is from visible to far infrared (0.55~18 μm); With the content of CsI increasing, the zero-dispersion wavelength of material decreases, in the value of 3.5 μm and 1.5 μm, corresponding to 20% CsI- and 40% CsI-chalcohalide glass, respectively. At the same time, the thermal stability of the two glasses is enough high, which is favorable for the preparation of low-dispersion mid-infrared fiber. Combined with effective glass purification method and high-temperature polymer-coating protection, a single refractive index chalcohalide glass fiber with a minimum loss of 8.2 dB/m was obtained.