Guo Zhenwu, Zhang Hongxia, Chen Xinwei, Jia Dagong, Liu Tiegen
College of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin 300072, China.
Appl Opt. 2011 Jul 10;50(20):3553-8. doi: 10.1364/AO.50.003553.
The principle of the mode cross coupling in polarization-maintaining fiber based on white-light interferometry was analyzed. The method of measuring the polarization mode coupling with a spatial Michelson interferometer was presented. Analysis and emulation were carried out for the vibration disturbance signal caused by the mechanical scanning and the influence the vibration imposed on the judgment of coupling intensity. The interference signal envelope is extracted by a Hilbert transform and fitted by a Gaussian least-squares method under the different scanning speed. It is indicated that the detection accuracy varies with the vibration amplitude, which varies with scanning speed. The best scanning speed of the system should be from 0.7 mm/s to 0.9 mm/s to achieve the minimum detection error.
分析了基于白光干涉法的保偏光纤中模式交叉耦合原理。提出了一种用空间迈克尔逊干涉仪测量偏振模耦合的方法。对机械扫描引起的振动干扰信号以及该振动对耦合强度判断的影响进行了分析和仿真。在不同扫描速度下，通过希尔伯特变换提取干涉信号包络并采用高斯最小二乘法进行拟合。结果表明，检测精度随振动幅度而变化，而振动幅度又随扫描速度而变化。系统的最佳扫描速度应为0.7毫米/秒至0.9毫米/秒，以实现最小检测误差。
