为了改善不同类型光纤熔接时的模场失配, 通过调整普通光纤熔接机的熔接参数, 对模场直径较小的光纤进行加热扩芯, 实现了10/130μm大模场面积双包层光纤和6/125μm单模光纤的低损耗熔接, 光纤耦合效率可达到91%, 并成功应用于自主研发的小型1064nm光纤激光器中。对利用光纤熔接机加热扩芯制作模场适配器进行了理论分析, 并用1064nm光纤激光器测量其实际传输损耗。实验结果表明: 采用普通光纤熔接机, 适当的调整熔接参数, 可以有效地提高大模场面积光纤到单模光纤的耦合效率, 为制作模场适配器提供了一种简单实用的方法。

In order to improve the fiber mode field mismatch between different types of fiber for splicing, the core of the single mode fiber is thermally expanded by adjusting the parameters of the optical fiber fusion splicer. The loss of the fibers fusion splicing is effectively reduced between the 10/130 μm LMA double clad fiber and the 6/125μm single-mode fiber. The efficiency from LMA double clad fiber to the single-mode fiber is improved to achieve 91%. It is successfully applied in the product of miniature 1064 nm fiber laser which is researched independently. Under the guidance of thermally expanded core technique, the fiber mode field adaptors with a fiber fusion splicer are fabricated and the actual loss of the adaptors with a 1064 nm fiber laser is measured. The experimental results demonstrate that the coupling efficiency with adjusting the parameters of the optical fiber fusion splicer is effectively improved. A simple and practical method for fabricating mold field adapters is provided.