基于解调技术的光纤激光传感器

Fiber laser sensor based on demodulation technology

为了提高检测分辨率和运行稳定性,研究了一种基于解调技术的光纤激光传感器。光纤激光传感器选用分布式布拉格反射结构,详细介绍了光纤激光传感器原理和光纤激光传感器高分辨率解调原理,依据干涉式传感原理对干涉信号的相位改变情况进行检测,获取受外界信号影响导致的激光器腔长的应变。给出设计的光纤激光传感器结构。通过波分复用器对光纤激光器形成的稳定窄线宽单频激光进行处理,删除抽运光。激光从波分复用器输出后接入光隔离器,通过1×2耦合器把激光划分成两束,将其中的一束接入光谱仪进行测试,将另一束添加至非平衡干涉仪。介绍了由3×3耦合器组成的迈克尔逊干涉仪,以3路输出的NPS方法和反正切方法为代表完成研究。实验结果表明,研究的基于解调技术的光纤激光传感器稳定性很高。

In order to improve the detection resolution and operation stability,a fiber laser sensor based on demodulation technology is studied. The fiber laser sensor selects distributed Prague reflectors. This paper introduces the principles of fiber laser sensor and high resolution demodulation. Based on interferometric sensing principle,detect the phase changes of interference signal to acquire the respond of laser cavity length caused by external influence. The design of the fiber laser sensor is given. Process the stable narrow width signal frequency laser caused by fiber laser through wavelength division multiplexer,and the pumping light is removed. After the laser is output from the wavelength division multiplexer,the laser is connected to an optical isolator,and the laser is divided into two beams through a 1 × 2 coupler. One of the beams is connected to the spectrometer for testing,and the other beam is added to the unbalanced interferometer. A Michelson interferometer consisting of 3 × 3 couplers is introduced,and the NPS method and the tangent method of 3 outputs are represented. The experimental results show that the fiber laser sensor based on demodulation technology has high stability.