利用半导体激光器的Lang-Kobayashi方程,对半导体激光自混合干涉系统的动力学特性进行了仿真分析。研究结果表明,当光反馈系数较小时,激光器处于稳定状态,外腔长度不影响系统的稳定性;当光反馈系数较大时,激光器将进入不稳定状态,对于不同的外腔长度,激光器的稳定状态将发生变化。为实现大量程的位移或距离测量,光反馈系数必须足够小才能保证在较大外腔长度变化范围内,激光器始终处于稳定状态。 Using the Lang-Kobayashi equation of the semiconductor laser, the dynamics characteristics of the semiconductor laser self-mixing interference system are simulated. The results show that when the optical feedback coefficient is small, the laser is in a steady state and the length of the external cavity does not affect the stability of the system. When the optical feedback coefficient is large, the laser will enter an unstable state. For different external cavity lengths, The steady state will change. In order to achieve large-scale displacement or distance measurement, the optical feedback coefficient must be small enough to ensure that the laser is always in a stable state within the range of larger external cavity length.