边发射半导体激光器自混合测速仪研究

采用边发射半导体激光器作为激光自混合速度测量系统的激光光源，针对不同表面类型、采样时间、注入电流、信号处理系统对自混合测速结果的影响进行实验研究和讨论分析。结果表明不同反馈表明和采样时间（0.1S,1S）均能满足高精度测速要求。同时，实验中采用合适的激光工作电流（激光器阈值电流1.1倍以上）并结合零点控制技术能够获得信噪比更大激光自混合测速信号。这些结论对深入分析自混合信号的产生机理以及半导体激光自混合测量系统的优化具有参考意义。

Self-mixing velocimeter using an edge emitting laser

Self-mixing interference produced by the feedback of light from a moved target into an Edge Emitting Laser (EEL) was experimentally investigated for sensing applications.  The self-mixing velocimeter with different types of surface，values of sample time and injection current, signal process system were also discussed. Results indicate that high precision requirement can be reached with different types of surface，values of sample time (0.1S,1S). Combined the experimental results of the self-mixing velocity measurement system, selecting proper injection current(above 1.1 times of threshold current) of EEL and null control technique can enhance Signal to Noise Ratio(SNR) of self-mixing signal. This conclusion can help us to improve the mechanism study and optimize the self-mixing vibration measurement system.