基于侧边抛磨光纤的侧面熔粘耦合的光纤耦合器

针对熔融拉锥法难以应用于制作特种光纤耦合器的情况,研究设计了一种适用于光子晶体光纤(PCF)或椭芯保偏光纤(ECPMF)等特种光纤耦合器制作的光纤侧边抛磨、侧面熔粘(FSA)耦合方法。通过建立仿真模型优化了光纤侧边抛磨的抛磨区包层剩余厚度等关键参数,利用侧边抛磨单模光纤(SMF)成功制作出FSA侧边抛磨光纤耦合器,并测试了光纤耦合器的相关特性参数。实验结果显示,侧面FSA耦合方法可制作耦合比(CR)为0～90%的特种光纤耦合器;所制作的光纤耦合器附加损耗(EL)小于0.5dB;在100nm光波长范围内,波长相关损耗(WDL)小于1dB;耦合输出端的偏振相关损耗(PDL)在光波长1310nm、1550nm处分别为0.30dB、0.45dB。研究结果验证了光纤侧边抛磨、侧面FSA耦合方法制作特种光纤耦合器的可行性,为有特殊要求的PCF或ECPMF等特种光纤耦合器制作奠定了方法基础。

A fused side-adhered optical fiber coupler based on side-polished fibers

Referring to the invalidity of fused tapering method in fabricating op tical fiber couplers based on special fibers,such as photonic crystal fiber (PCF) and elliptical core polari zation maintaining fiber (ECPMF),a new fabrication method of fused side-adhered (FSA) coupling based on a pair of side-polished fibers is proposed.Numerical model is set up and simulation analysis is performed to optimize the key param eters of side polished fiber,like the remaining thickness in the polished area.Using the proposed method and the optimized parameters,we conduct experiments to fabricate a single mode fiber coupler and characterize its performance.The results show that fiber couplers with various coupling rate from 0% to 90% can be available w ith the FSA method,excess loss and output ports wavelength dependence loss are less than 0.5dB,and 1dB,respec tively,and the coupled port output polarization dependence loss is 0.3dB at wavelength of 1310nm and 0.45dB at 1550nm.This paper demonstrates the feasibility of the FSA method we propose,and supplies theor etical and technical basis in fabricating optical couplers based on special fibers for special requirements.