Primary Shock Calibration Using Laser InterferometryLiang Zhiguo,Li Xinliang,Lian Dahong National Laboratory of Metrology ＆ Measurement of Changcheng Institute of Metrology ＆ Measurement, Beijing 100095, ChinaAbstract:An accelerometer shock calibration method by using grating laser interference technique is described in this paper. The shock acceleration value is directly and absolutely acquired from the basic quantity and unit （time and length）. The principle of the differential grating laser interferometer shock calibration device are introduced. Its characteristic is through impulse stimulation by using the grating width, diffraction series, laser wavelength, and the Doppler frequency shift to determine the shock velocity and the shock acceleration instantaneous value. By employing a frequency demodulation method of FM signal, the Doppler frequency shift of laser is gained, the time resolution of this method is just one sampling period, and both the Robust and convergent of this method are excellent, its precision is good enough. By using movement least square beeline segment, the paper realized the differential operation, and obtained the shock velocity and the shock acceleration instantaneous value. Finally, an experimental result is given.[著者文摘]
Key words:metrology, grating laser interferometer, shock calibration frequency demodulation.
