利用传输矩阵法和龙格－库塔法分析光纤布喇格光栅的反射谱和时延特性，无法得到输入信号变化时光栅的动态响应。为了计算光纤光栅的动态响应，利用坐标变换结合有限差分法求解耦合波方程，在此基础上计算了光纤布喇格光栅在连续波与高斯脉冲输入的动态响应特性，并与龙格－库塔法比较，结果证明了此算法的正确性。可以利用本文中提出的方法分析输入信号在光纤光栅中的动态传输特性。

Because it is impossible to use the matrix method and Runge-Kutta method to acquire the dynamic response of fiber Bragg grating(FBG)when analyzing the reflection spectrum and time-delay characteristic of FBG,it is proposed to compute the dynamical response characteristic of FBG with respect to the input of continual wave(CW)and Gaussian pulse,by means of coordinate transformation combined with finite difference method. The acquired reflectivity under conditions of the input of CW keeps in accord with that acquired by the Runge-Kutta method,which proves the validity of this method.