光纤激光器自混合干涉效应研究

针对光纤激光器自混合干涉传感应用,研究了光纤激光器自混合干涉特性,运用四镜法布里-珀罗腔模型对掺铒线形腔光纤激光器自混合干涉效应进行了理论分析,对不同反馈水平下的自混合干涉信号进行了数值模拟,获得了光反馈条件下光纤激光器输出特性.外腔长度的改变会调制激光器的输出强度,外腔长度变化半个波长,对应一个干涉条纹,弱反馈条件下,由反馈引起的激光器的频率变化可以忽略.设计了基于光纤激光器的自混合干涉实验,实验结果和理论分析相符合.此研究结果为进一步开展光纤激光器的自混合干涉传感应用研究奠定了理论与实验基础.

Self-mixing interference effect based on fiber laser

For the sensing applications based on the self-mixing interference technology of fiber laser, the self-mixing interference in the linear cavity fiber laser is theoretically analyzed through a four-mirror cavity model. The output power and frequency equation are deduced, and the behaviors of the laser under different optical feedback strengths are analyzed and simulated as well. The intensity of the laser is modulated by the length of the external cavity, and one fringe of the signal corresponds to the displacement of half wavelength of the target. Experimental setup is developed to validate the theoretical analysis. The obtained results provide both the theoretical and experimental basis for further studying self-mixing interferemetric sensing applications of fiber lasers.
Keywords：fiber laserself-mixing interferencefiber sensing