改变光栅折射率实现双波长采样光栅的方法

Dual-Wavelength Sampled Fiber Bragg Grating by Changing Refractive Index of Fiber

提出了一种新的基于采样光纤布拉格光栅(FBG)的双峰(DW)滤波器实现方法。通过改变采样之间的直流折射率,在FBG中引入相移;利用占空比为1的余弦函数采样,抑制除±1级以外的所有波长通道。该设计制作方法具有波长设计灵活、制作精度要求低与成本低的优点。对均匀直流相移光栅、采样直流相移光栅与传统离散相移光栅进行了比较与实验制作,结果与理论相吻合。实现了波长间隔为0.08nm的DW滤波器,证明了该方法的可行性。

A novel dual-wavelength（DW） sampled fiber Bragg grating（FBG） is proposed.Phase shift between two adjacent FBG units is achieved by increasing direct current（DC） refractive index of FBG.The FBG with only identical ±1 order reflective spectrum is optimized with cosine sampling function.This method has the advantages of flexible wavelength design,low fabrication precision and low cost.Comparison between uniform DC phase shift FBG,sample DC phase shift FBG and traditional discrete phase shift FBG is made.Uniform DC phase shift FBG and sample DC phase shift FBG are fabricated,which show a good agreement with theory.DW filter with channel spacing 0.08 nm is fabricated,and the experiment results verify the feasibility of this proposed method.