基于全光纤自混合干涉技术的微振动测量研究

为了解决自由空间自混合干涉测量系统工作距离短、易受环境干扰等不足,采用全光纤传光、光纤自聚焦透镜收集反馈光,设计了一套全光纤自混合干涉测量系统;建立了反射面为镜面时自聚焦透镜收集效率的理论模型,在理论上论证了全光纤自混合干涉测量系统的可行性;最后搭建了全光纤自混合干涉测量系统,并以铝膜作为反射面,进行了微振动实验研究.结果表明,该系统能获得较好的实验信号,可以解决自由空间自混合干涉测量系统工作距离短、易受环境干扰等问题.

Tiny vibration measurement based on all-fiber self-mixing interference

In order to overcome disadvantages of a free-space self-mixing system, such as short working distance and susceptivity to the environment, an all-fiber self-mixing interference system was designed using a fiber to transmit light and a gradient refractive index(GRIN)lens to collect feedback light. The collection efficiency model of the GRIN lens with a mirror reflecting surface was built. Then the feasibility of an all-fiber self-mixing interference system was theoretically proved. Finally, the experimental facility was established. Experiments were carried out with aluminous foil as reflecting surface. The experimental results show that this new instrument can acquire fine signal and it also has the ability of remote measurement.