光纤光栅梳状滤波器及其在新型可选波长激光器中的应用

对现有在同～段光纤上多次写入光栅制成光栅梳状滤波器的方法进行了改进，利用增加光栅长度，精确控制不同光栅的曝光时间，并结合调整光栅实际写入长度的方法，制成了不均衡度小于5％、最低峰值反射率高于95％的光纤光栅梳状滤波器；同时提出了一种新颖的可选波长光纤激光器结构。采用由上述方法制作出的反射率均衡的光纤光栅梳状滤波器和可调光滤波器结合在一起进行波长选择，实现了波长的快速准确选择，同时各个波长激光的输出特性稳定，功率均衡性好，边模抑制比大于50dB。

Fiber Gratings Comb Filter and Its Applications in Novel Wavelength Selectable Fiber Laser

The traditional method to write several gratings in the same fiber has been improved by increasing the grating length, controlling the writing time concisely and adjusting the effective length of grating slightly. High-quality fiber grating comb filter has been made with non-uniformity of reflectivity between different wavelengths less than 5% and reflectivity of each wavelength larger than 95%. Based on the newly made fiber grating comb filter, a novel wavelength selectable fiber laser is proposed. Tunable optical filter combined with the comb filter realizes the fast and accurate wavelength selectivity. The laser output characteristics are very stable. The output power uniformity of the laser is also very good and the side-mode suppression ratio is larger than 50 dB for each wavelength.