激光多普勒扭转振动测试技术的研究

Research on the Torsional Vibration Measurement with Laser Doppler Technology

提出了一种差动式可辨向激光多普勒扭转振动测试仪 ,计算并分析了激光多普勒技术的双相检测和矩形光栅的衍射光强分布。采用相位光栅作为光学混频器件 ,提高了测量的信噪比并充分地利用了光能。实验表明 ,该系统能有效地实现旋转轴可辨向扭转振动的测量 。

A new difference Laser Doppler Vibrometer with directional discrimination is introduced. Two-phase detecting technique used to distinguish the direction and the intensity distribution of the phase grating diffraction pattern is analyzed. The phase grating is a frequency-mixing device that can get high SNR signals. The experiments prove that the system can be used to measure torsional vibration and distinguish the rotating direction of the rotor, which can reach a high accuracy.