弯曲对长周期光纤光栅透射特性的影响

Effect of Bend on Transmission of Long-period Fiber Grating

讨论了长周期光纤光栅弯曲时引起的波导弯曲、光纤截面变形和纤芯折射率分布改变等对其透射特性的影响。用等效直倾斜二次方啁啾的长周期光纤光栅理论,分析研究了光栅轴向倾斜对长周期光纤光栅透射特性的影响,给出了等效光栅的周期、啁啾系数的近似公式,用传输矩阵方法进行了数值计算。

The effect of optical loss in bent waveguide, change of fiber transverse section and index distribute on transmission of bent long-period fiber grating (LPFG) are discussed in this paper. The transmission of LPFG is analyzed by the means of equalizing the bent LPFG to a tilted quadric chirp LPFG. The approximate formula of period and chirp factor of effective grating is obtained. The transmission with different bent LPFG is numerically calculated by the transfer matrix method.