卤化银多晶光纤传输CO2激光性能的研究

通过采用高真空熔炼、反应气氛下区域融熔和高真空石英安瓿内单晶生长等特殊工艺方法对卤化银原料进行提纯，并用热挤压成型方法制得卤化银光纤．本文研究了卤化银原料的提纯和光纤成型工艺对损耗的影响，研究结果表明，增加提纯次数可降低卤化银光纤预制棒的吸收系数．通过合理控制工艺参数，提纯后的卤化银原料制成的光纤预制棒，经ＣＯ_２激光量热计法测量在１０．６μｍ处的吸收系数＜５×１０^－4ｃｍ^－１，热挤压成型的光纤在１０．６μｍ处的损耗为０.３～０.５ｄＢ／ｍ，直径φ１０ｍｍ、长度１．６４ｍ的光纤可传输ＣＯ_２激光功率＞２０Ｗ．

Characteristics of Polycrystalline Silver Halide Fiberfor Transmitting CO2 Laser

The silver halide was purified by melting at high vacuum, zone melting with reactive atmosphere and crystal growing in quartz ampoule with high vacuum. The silver halide fibers were made by hot extrusion. The effects of the purification of silver halide and its fiber preparation method on transmission loss were studied. Experiment results show that the increase of the number of times of the starting material purification will cause the decrease of absorption coefficient of silver halide preform. A high quality preform was obtained by a reasonable technology. The absorption coefficient of the purified　silver halide preform measured by CO₂ laser calorimeter is less than 5×10^-4cm^-1. The transmission loss of the silver halide fiber is 0.3--0.5dB/m when measured by CO₂ laser beam at 10.6μm. Its output power of transmitting CO₂ laser beam is more than 20W in the fiber of 1.0mm diameter and 1.64m length.