实验研究了外部光注入分布反馈(DFB)激光器的非线性动力学行为，并给出了其输出特性随注入光强度和频率失谐量变化的动力学特征图。实验结果表明，激光器的动力学行为对外部的微扰十分敏感; 在不同外部光注入条件下，激光器可以呈现出单周期、倍周期、多周期以及混沌等多种非线性动力学特征; 在注入光强度和频率失谐量变化空间存在三个复杂动力学区域; 激光器表现出的复杂动力学行为总是与周期行为有关; 当激光器处于复杂动力学区域时，其频谱为连续谱，在连续谱上存在多个明显的峰，所对应的频率定义为特征频率，特征频率的大小不随注入光的强弱以及频率变化。

The nonlinear dynamic characteristics of distributed feedback (DFB) semiconductor lasers subjected to external optical injection have been investigated experimentally, and the output dynamical characteristics are mapped as a function of the power of optical injection and the frequency detuning between the injection frequency and free-running frequency of the unperturbed DFB semiconductor laser. Experimental results show that DFB semiconductor lasers are very sensitive to external perturbation and can exhibit periodic, chaos and other complex nonlinear dynamical characteristics when subjected to different external optical injection. There exist three regions of complex dynamics in the map. The complex dynamics is always related to the multi-periodic dynamics. When the laser exhibits complex dynamic, its spectrum is continuous spectrum, and there are several peaks in the spectrum. The magnitude of frequency that the peaks correspond to respectively has nothing with the power and the frequency of injection field.