为了提高激光时间波形测量系统的抗干扰能力,建立了激光脉冲在光纤中的传输物理模型,分析了纳秒脉冲在光纤中的线性传输特性,对影响脉冲传输特性的因素进行了系统评价。采用空气与光纤传输进行比对的方法,实验测试了激光脉冲经过不同长度的单模和多模光纤传输后的脉冲波形,得到脉冲展宽在允许的测量误差范围内所需的阈值条件。结果表明,该研究对神光-Ⅲ主机激光脉冲时间波形测量的设计具有重要的意义。

For the propose of improving the anti-jamming ability of a laser pulse shape measuring system,the laser pulse propagation model was established,the linear characteristics of a nanosecond pulse propagating in fibers were analyzed,and factors affecting the pulse transmission characteristics were evaluated systematically. The laser pulse shape was measured with a nanosecond laser pulse propagating through single and multi-mold fiber in different length. The width of the pulse transmitted by the fiber was compared to that of a fraction of the pulse propagating over an air path. The critical condition of pulse broadening acceptable within measuring error was obtained. The conclusion provides guidance to design the laser pulse shape measuring system of the SG-Ⅲ laser facility.