用于机械振动实时监测的光纤光栅有源传感装置

把一对中心反射波长分别为1562.11nm和1562.71nm的光纤光栅粘贴在均质、等厚、等腰三角形悬臂梁上下表面作为环形腔光纤激光器端镜，当机械振动激励自由端时，通过观测激光输出脉冲，地施加于自由端的机械振动的频率进行了实时监测；观察两光栅波长漂移量差值的变化，可在0～6.1mm的范围内判断所测振动的振幅。低于100Hz时，实验结果与实际值基本吻合。

A Novel Active Fiber Bragg Grating Sensor System for Monitoring Mechanical Vibration in Real-Time

A pair of fiber Bragg gratings with the wavelengths of 1562.11 nm and 1562.71 nm, respectively, are used as the end reflectors of a constructed linear cavity fiber laser. They are epoxied onto the upper and lower surfaces of an employed uniform density and thickness isosceles triangle cantilever beam axially. As a strain agent, the beam makes the wavelength shifts of both gratings be changeable, and therefore lead the laser producing pulses. The real time measurements of the frequency of the mechanical vibration applied on the free end of the beam are demonstrated by observing the pulses. Within the range of 0～6.1 mm, the amplitude of the vibration can be estimated by observing the wavelength shift difference between two gratings. The measured results have been demonstrated to be in good agreement with the actual values under the frequency of 100 Hz.