采用Nd∶YAG激光对全石英多模光纤进行激光诱导损伤实验,结果全部为光纤端面损伤, 主要是由光纤端面的杂质缺陷引起的。通过对激光损伤形貌的分析, 明确光纤端面损伤机理。采用Matlab对光纤损伤端面进行图像处理, 获得光纤端面损伤点的大小、出现频率和位置分布的统计特性。通过分析发现,光纤端面损伤点位置分布服从一定的规律, 光纤前端面和后端面不同; 光纤端面不同大小损伤点出现频率服从高斯分布; 注入激光特性参数决定光纤前端面损伤特性, 光纤传能特性以及光纤端面质量决定其后端面损伤特性。

The experiments of high peak pulsed laser-induced damage to fused-silica fibers have been carried out. The experimental results show that all the damage sites accrued on the fiber end-faces. The morphologies of damaged fiber end faces are observed and recorded using metallurgical microscope. Micrographs of fiber end faces are processed using a Matlab program; the distribution characterizations of damaged sites on fiber end faces are obtained. According to the computing results, we find that the damage sites distribution obey certain regularities, which are different between on the input end faces and on the output end faces; The sizes of damaged sites obey normal distribution; The location distribution of damaged sites is strongly related to input or output laser characterization; The morphologies of damaged fiber end faces are strongly related to the mechanism of laser-induce damaged to fiber end faces.