This paper deals with a systematical analysis and an algorithm of attenuation characteristics of a light attenuator combined by n pieces of polarizers （n-LACP） whose extinction ratios are different from each other. ...This paper deals with a systematical analysis and an algorithm of attenuation characteristics of a light attenuator combined by n pieces of polarizers （n-LACP） whose extinction ratios are different from each other. The attenuation ratio expression of a two-LACP is deduced. We find that the monotonic attenuation interval depends on the first polarizer and that the attenuation range depends on the second one. For the three-LACP, a method for obtaining a monotonic attenuation interval is proposed. Moreover, the attenuation ratio expression is demonstrated. Analysis and experiment show that when the initial status of the three-LACP is at the maximum output, if the second or third polarizer rotates alone, the minimum attenuation ratios can reach K2^-1 and K3^-1, respectively, and if the first polarizer rotates, a minimum attenuation ratio of K2^-1K3^-1 can be obtained （K1, K2 and K3 represent the extinction ratios of the three polarizers in turn）. Furthermore, the attenuation ratio expression of n-LACP and the relevant attenuation characteristics are proposed. The minimum attenuation ratio of an n-LACP is （K2K3 ... Kn）-1.展开更多
针对布里渊光时域反射型(BOTDR)分布式光纤传感系统中脉冲光源消光比易受偏置电压漂移影响的问题,本文提出了一种结合双电极串联结构电光调制器(EOM)及"扫描?步进跟踪"算法的脉冲光源消光比自动控制方法。实验结果表明,该方...针对布里渊光时域反射型(BOTDR)分布式光纤传感系统中脉冲光源消光比易受偏置电压漂移影响的问题,本文提出了一种结合双电极串联结构电光调制器(EOM)及"扫描?步进跟踪"算法的脉冲光源消光比自动控制方法。实验结果表明,该方法可将EOM输出脉冲光的消光比稳定在50 d B以上。在150 min的测试时间里,输出脉冲光消光比的最大值为52.4 d B,最小值为51.1 d B,波动值仅为1.3 d B。该方法对BOTDR光纤传感系统及高功率激光驱动装置等设备中脉冲光源性能的提升具有重要意义。展开更多
基金Project supported by the Technological Innovation Project of Air-to-Air Missile Institute of China (Grant No.5S85000FS)
文摘This paper deals with a systematical analysis and an algorithm of attenuation characteristics of a light attenuator combined by n pieces of polarizers （n-LACP） whose extinction ratios are different from each other. The attenuation ratio expression of a two-LACP is deduced. We find that the monotonic attenuation interval depends on the first polarizer and that the attenuation range depends on the second one. For the three-LACP, a method for obtaining a monotonic attenuation interval is proposed. Moreover, the attenuation ratio expression is demonstrated. Analysis and experiment show that when the initial status of the three-LACP is at the maximum output, if the second or third polarizer rotates alone, the minimum attenuation ratios can reach K2^-1 and K3^-1, respectively, and if the first polarizer rotates, a minimum attenuation ratio of K2^-1K3^-1 can be obtained （K1, K2 and K3 represent the extinction ratios of the three polarizers in turn）. Furthermore, the attenuation ratio expression of n-LACP and the relevant attenuation characteristics are proposed. The minimum attenuation ratio of an n-LACP is （K2K3 ... Kn）-1.
文摘针对布里渊光时域反射型(BOTDR)分布式光纤传感系统中脉冲光源消光比易受偏置电压漂移影响的问题,本文提出了一种结合双电极串联结构电光调制器(EOM)及"扫描?步进跟踪"算法的脉冲光源消光比自动控制方法。实验结果表明,该方法可将EOM输出脉冲光的消光比稳定在50 d B以上。在150 min的测试时间里,输出脉冲光消光比的最大值为52.4 d B,最小值为51.1 d B,波动值仅为1.3 d B。该方法对BOTDR光纤传感系统及高功率激光驱动装置等设备中脉冲光源性能的提升具有重要意义。
