反射谱具有三角形形状的光纤光栅在光纤传感等领域中具有重要的应用前景。利用遗传算法设计出了产生三角形光谱分布的光纤光栅的耦合系数沿光纤的分布。计算表明 ,三角形光谱光纤光栅是可以实现的 ,其反射带宽可以通过光栅的啁啾量进行调节 ,常周期的三角光栅反射带宽小 ,变周期的三角光栅反射带宽大 ,其带宽同其啁啾量大致相等。实验中 ,采用光束扫描法制备了反射底宽为 0 .77nm三角形光谱的光纤光栅。 The fiber grating with the triangular shape of the reflection spectrum has an important application prospect in the fields of optical fiber sensing and the like. The distribution of the coupling coefficient of fiber grating along the fiber is designed by using genetic algorithm. The calculation shows that the triangular fiber grating can be realized, its reflection bandwidth can be adjusted by the chirp of the grating, the reflection bandwidth of the triangular grating with the constant period is small, the reflection bandwidth of the triangular grating with varying period is large, and its bandwidth is the same as its chirp Roughly equal. In the experiment, a fiber grating with reflection bottom width of 0.77nm triangular spectrum was prepared by the beam scanning method.