利用激光多普勒外差原理对振动物体测量及分析

为了测量低频振动物体频率和振幅,采用激光多普勒测量和外差相干检测方法,建立一个利用激光外差干涉技术测量多普勒效应的实验,进行了理论分析和实验验证,取得了频率标准偏差数据。结果表明,系统检测物体振动频率,并对振源频率500Hz进行测量并且验证有效性,测量标准偏差小于5.610-8;系统信号探测强度和物体振幅呈线性关系,证明随压电陶瓷电压降低探测振幅强度减小。这一结果对了解振动目标特性是有帮助的。

Vibration measurement and analysis by means of laser Doppler heterodyne principle

Laser Doppler measurement methods and coherent heterodyne detection were adopted to measure the frequency and amplitude of low frequency vibration. An experiment setup was built, based on which the Doppler effect was measured with a heterodyne laser interferometer and the standard frequency deviation was obtained. The results shows that the system can detect the object vibration at less than 500Hz frequency, and the measurement standard deviation is less than 5.610-8; The strength of the system detection signal is linear with the amplitude of object, demonstrating that the intensity detection amplitude reduces with the drop of the voltage of the piezoelectric ceramic. The result is helpful to know the characteristics of vibration targets.