针对光纤激光传感器信号解调过程中,干涉仪输出干涉条纹可见度受输入光偏振态变化以及两臂单模光纤双折射效应的影响,介绍了一种简单的光纤干涉仪消除偏振衰落技术,通过在Michelson光纤干涉仪上加两个法拉第旋转镜来提高输出条纹可见度。使用琼斯矩阵法对干涉仪系统进行理论计算,证明法拉第旋转镜旋转角度在理想的45°附近时能达到很好的消偏振效果,并通过实验进行了有效地论证。
During the wavelength demodulation of fiber laser sensors, random fluctuations in states of polarization of the interferometer beams induce fading of the interferometric fringe visibility, that effects the reliability of the system. To improve the fringe visibility of output signal, a simple and useful way is proposed which called the Faraday rotator mirror method. In theory domain, take the Jones matrix into calculated, seemed that when the degrees of Faraday rotator mirrors around 45o, the results would suit the system, and this had been finely testified by experiments.