全光纤傅里叶变换光谱仪消偏振衰落技术研究

针对全光纤傅里叶变换光谱仪中光束偏振态在双折射影响下带来的干涉信号"偏振诱导衰落"现象导致测量光谱畸变的问题,根据偏振光学原理,分析了光纤应力、弯曲和扭曲导致的双折射对传输光束偏振态的影响,找到了FFTS在测量宽谱光源发射谱时出现谱线畸变的原因,提出了建立偏振态反馈控制系统来稳定干涉信号可见度的方法.实验结果表明,该方法消除了偏振态变化对测量光谱的影响.

Elimination of Polarization Fading in Fiber Fourier Transform Spectrometer

For the problem of spectral distortion in all fiber Fourier transform spectrometer caused by the phenomenon of polarization fading on the output interferometric signal, the effect of optical fiber birefringence which were induced by stress, bending and twisting to light polarization state were analysed by Polariztion Optics theory,and find the reason of spectral distortion in FFTS. Finally,in order to stabilize the fringe visibility, the method to establish feedback control system of polarization state was proposed. Experimental results demonstrate that the impact of polarization state change has been eliminated by the method.