一种新型光纤光栅无啁啾调谐方法

分析了基于弹性梁的光纤光栅调谐原理，引入了轴向直变传递系数的概念，提出利用部分纯弯曲调谐方法，可实现光纤光栅宽带无啁嗽调谐。在实验中，利用部分纯弯曲调谐法，获得了20．1nm的光纤光栅无啁嗽调谐范围，调谐线性拟合度为0．9996，调谐过程中光栅反射谱的3dB带宽变化小于0．07nm，峰值反射率变化小于0．2dB，基本无啁嗽现象产生，实验结果和理论分析一致。

In this paper, the principle of fiber Bragg gratings (FBG′s) tuning method based on elastic beam is analyzed, an axial strain transfer coefficient is introduced, and a wide-band FBG tuning without chirp by the method of part pure bending is proposed. In experiment, the chirp-free tuning wavelength of 20.1 nm, using part pure bending method was achieved. During the whole tuning process, the linearity was 0.9996, the 3-dB reflection bandwidth and the reflection index showed little variations less than 0.07 nm and 0.2 dB, respectively. There was almost no chirp appearing, and the experiment consists with theory analysis well.