双折射波导偏振耦合的短相干干涉测量

保偏光纤内部具有的高双折射，使其在内部传播的主模和耦合模之间存在一定的光程差。研究了高双折射波导中连续偏振耦合分布和分立点耦合的白光干涉测量法，推导出一种简明使用的公式，求出双折射波导的保偏参数，并且根据调制解调相关原理精确测量耦合点的强度和位置。实验测量了国产类矩形保偏光纤以及光纤偏振器。该方法最突出的优点是采用非破坏性方法测出保偏波导的每个局部的保偏参数，可用于检测集成波导器件和保偏光纤的质量、双折射波导之间的主轴对准、分布式光纤应变传感器等领域，并且可作为保偏光纤生产和使用的一种有效检测方法，大大提高集成波导器件及相关传感器的性能。

Short coherent interferometry of polarize coupling in birefringent waveguide

The main polarization mode and coupling mode in polarization-maintaining fiber (PMF) have some optical path difference because of the internal birefringence. White-light interferometry for testing continuum polarized coupling distributing and discreting polarized coupling distributing in high birefringent waveguide was investigated. The polarization-maintaining parameter was obtained and a concise formula was derived. It can be used to measure the intensity and position of the coupling point accurately according to the relevant theory of modulation and demodulation. PMF and the optical fiber polarizer were measured as examples. The new approach can be utilized to test integrated waveguide elements, PMF, the axis alignment between birefringent waveguide, distributed optical fiber sensors, etc, The most prominent advantage of this method is to measure the polarization-maintaining parameter without any destruction to PMF. It can be used as an effective testing tool in PMF manufacture and application. With the help of this detection method, the performance of optical fiber polarization devices and optical fiber sensors is improved significantly.