中文摘要：

根据光纤的消逝场耦合模理论，论述了熔融拉锥型光纤耦合器的工作原理；以六轴型熔融拉锥机为实验平台，研究了熔融拉锥法制作3dB单模光纤耦合器的过程；分析了拉伸速度与附加损耗厦损耗偏差的关系，发现拉伸速度为150μm／s时，耦合器的性能达到最优；此外，利用光学测试系统测试了光纤耦合器的插入损耗、附加损耗、方向性与均匀性等光谱特性参数。研究结果表明，所得实验结果与耦合理论分析结果吻合，说明该方法具有制作过程简单、附加损耗低、环境稳定以及成本低麻等优点。

英文摘要：

The coupling-mode mechanism of fused bieonieal taper was discussed based on tiber s evanescent field coupling theory. The facture process of 3 dB single-mode fiber coupler was studied by making use of the experimental platform of a 6-axis optical fiber coupler machine and the method of the fused biconicaq taper. The relation between drawing speed and excess loss and tolerance of loss was analyzed. It is found that the fiber coupler has good performance when the drawing speed is 150 μm/s. The performance parameters of fiber coupler, such as insertation loss, excess loss, directivity and uniformity, were tested using optical test system. It is indicated by a large number of experiments that the experimental result is in good agreement with analysis of coupling-mode theory. The experiment result also shows that the manufacture technology has some advantages, such as the simple facture process, low excess loss the environmental stability and the low cost.