W型色散光纤带通滤波特性的研究  

Study of Band-Pass Filtering Characteristics of W-Type Dispersive Fibers

作　　者：宋鹏[1,2] 季敏宁[1,2] 余燕[1,2] 

机构地区：[1]上海大学电子物理研究所,201800 [2]上海大学特种光纤与光接入网省部共建重点实验室,上海200072

出　　处：《光学学报》2011年第1期66-72,共7页Acta Optica Sinica

基　　金：上海市教委创新基金(09YZ31);国家自然科学基金(60777031);上海市重点学科和科委重点实验室项目(S30108;08DZ2231100)资助课题

摘　　要：结合色散光纤在线滤波和W型光纤的长波长截止性能,研究了W型色散光纤的带通滤波特性。选取SiO2作为纤芯,一定掺杂浓度的SiO2-F和SiO2-B2O3分别作为内外包层,经过设计,实现了带通滤波功能。通过有限元法仿真及数值计算,得出了基模的能量损耗谱及通带内外各个波长处的横截面能量分布图,其截止波长和带宽可以通过控制掺杂浓度和结构参数来调整。此外还进一步分析了纤芯半径大小及中心空气孔凹陷的存在对滤波特性的影响,结果表明,减小纤芯半径和增大空气孔能减小带宽和增大通带边缘的陡度。Band-pass filtering characteristics of W-type dispersive fiber are studied by combining online filtering dispersive optical fiber with W-type fiber which is long wavelength cutoff.A band-pass filter can be achieved by appropriate structure composed of SiO2 core,SiO2-F inner cladding and SiO2-B2O3 outer cladding respectively.According to finite element method simulation and numerical calculation,energy loss of fundamental mode and energy distributions at some wavelength of the stopped band or passband can be obtained,and the cutoff wavelength and bandwidth can be adjusted by controlling the dopant concentration and structure parameters.The influence of the core radius and the central air hole on the filtering performance is analyzed.The results show that decreasing the core radius or enlarging the air hole will reduce bandwidth and increase the passing band edge steepness.

关 键 词：光纤光学 带通滤波 有限元法 W型色散光纤 

分 类 号：TN252[电子电信—物理电子学]