激光束的锥台光纤传输

分析了锥台光纤的传输特性,建立了高斯近似模型，采用模场耦合理论，计算了锥台光纤的功率转换效率。并在激光器的输出光波长为532 nm，多模光纤的数值孔径为0.11，纤芯半径为12.5 μm条件下对细端半径分别为（4±1），（5±1），（6±1），（7±1）和（8±1） μm的锥台光纤的转换效率进行了实验测定。提出利用锥台光纤的圆柱形多模光纤部分传输光功率，锥台部分保证光束质量的传输方案，在保证光束质量的同时能传输较高的光功率。

Tapered fiber relay for laser beam transportation

Based on a mode field coupling theory, a Gaussian approximation model to calculate the conversion efficiency of tapered fiber is presented. The simulation result is discussed and an experiment is conducted with 532 nm laser, multi-mode fiber (numerical aperture is 0.11, radius is 12.5 μm) and tapered-fiber (numerical aperture is 0.11, radius is (4±1)，(5±1)，(6±1)，(7±1) and (8±1) μm respectively) to measure conversion efficiency of tapered fiber. Good agreement is obtained between the experimental results and the theoretical calculations. A tapered fiber relay system is proposed to transport a laser beam with high power and good beam quality.