宽带弯曲不敏感多模光纤

Wide-band Bending Insensitive Multimode Fiber

针对以太网数据对多模光纤传输性能要求不断提高的问题,文章从材料组成和剖面结构设计的角度,提出了改善宽带弯曲不敏感多模光纤性能的措施。一方面通过优化纤芯掺杂元素的浓度分布,降低最佳剖面折射率分布参数αopt与波长之间的敏感性,提高多模光纤的带宽特性;另一方面在芯—包界面处采用连续可调节剖面结构(内包层),该结构不仅可以减小芯层和凹陷包层粘度差对光纤性能的影响,而且还可以通过界面结构的调节,非常有效地改变高阶模的时延,消除凹陷对光纤带宽性能的影响。测试结果表明,该新结构光纤不仅具有较宽的带宽特性,还具有较低的弯曲损耗。

In order to further improve the multimode fiber transmission performance in the Ethernet,the paper proposes to improve the performance of wide-band bending insensitive multimode fiber considering the material composition and profile structure design.By optimizing the concentration distribution of the doped elements in the core,the sensitivity between the parameter of optimal profile refractive index distributionαopt and the wavelength is reduced,and the fiber bandwidth characteristics is improved.In addition,the new design contains an inner cladding which can adjust the profile structure continuously at the interface of core and cladding.The continuous adjustable structure can reduce the influence of viscosity difference between the core layer and the trench on the fiber performance.It can also alter the delay of higher-order modes very effectively to eliminate the impact of trench structure on fiber bandwidth characteristics,by adjusting inner cladding profile.The results show that the fiber with the new structure has not only higher bandwidth characteristics,but also lower bending loss.