报道了在常规熔锥型单模光纤定向耦合器工艺基础上，以氢氟酸腐蚀法，将两光纤耦合区直径腐蚀成适当比例，用水平直接熔融拉锥系统，将耦合区域拉制成非对称臂组合波导，从而获得了具有宽频带特性、且尺寸较小的单模光纤定向耦合器。实验结果说明；通过控制耦合区长度，可以使耦合器耦合功率在某个特定波长附近、预定小于１００％分束比上具有相当平坦（宽带）特性；从而，通过控制组合波导的不同直径比，可望得到不同分束比宽带耦合器。 The paper reports the corrosion of hydrofluoric acid on the basis of the conventional single-mode fiber-optic directional coupler with fused-taper. The diameter of the two fiber-optic coupling regions is etched to an appropriate ratio. The horizontal direct taper system is used to pull the coupling region into non- The symmetric arm combines waveguides to obtain a single mode fiber directional coupler with a wide frequency band and a small size. Experimental results show that the coupler coupling power can be controlled by controlling the length of the coupling region so that the coupler coupling power has a relatively flat (broadband) characteristic at a predetermined splitting ratio less than 100% at a certain wavelength. Therefore, by controlling different diameter ratios of the combining waveguide, It is expected to get different splitting ratio broadband coupler.