腐蚀后的新型长周期光纤光栅特性研究

报道了高频CO2激光脉冲写入的长周期光纤光栅的腐蚀特性,即LPFG的谐振波长随腐蚀时间的变化线性地向长波方向漂移,而其谐振峰幅值变化却很小.首次对腐蚀后的长周期光纤光栅的基础特性进行了研究,发现其温度、应变、扭曲特性都未发生改变,而弯曲灵敏度比未腐蚀时的要小.从而得出了可用腐蚀来调整长周期光纤光栅谐振波长而不改变其特性的结论.

Characteristics of the Etched Long-period Fiber Gratings

Etching characteristics of the LPFGs written by high-frequency CO_2 laser pulses are demonstrated. The experimental results show that the resonant wavelength of the LPFGs shifts linearly with the etching time,while the resonant peak amplitude varies little. Furthermore,the basical characteristics of etched LPFGs are demonstrated for the first time. It came out that the characteristics of temperature,strain and distortion change nothing between un-etched and etched cases except that the bending characteristics become less sensitive. So that a conclusion was drawn that such a etching method could be used to adjust the resonant wavelength of the LPFG but not change its characteristics.