激光干涉信号的位置及偏差提取

Research on Laser Interferential Signals Processing to Obtain Position and Position Error

为提高傅里叶变换光谱仪的性能,提出了一种精密的激光干涉信号位置及位置偏差提取方法。正交激光干涉信号经过放大,滤波,整形,成为正交数字信号,判向后在可逆计数器实时计数,DSP每隔固定时间读取一次计数器的值,获得位置信号。利用同步脉冲获得实际位置值,并将原误差减小后转移到参考位置值,使位置偏差的精度大大提高,相应提高了控制精度,同时使得实际位置的测量误差达到纳米级。

To improve the performance of Fourier transform spectrometer, precise position and position error measurement methods are proposed. The vertical laser interferential signals are changed into vertical digital signals through amplifier, filter and conditioning circuits, one of which is counted in reversible counter after direction judgment. Digital signal processing （DSP） chip read the counter in uniform intervals to attain real position value. Synchronous pulse is used to get real position value, and the measurement error is transferred into reference position error after being decreased thousands of times, which improve the precision of position error and the controller apparently,meanwhile,the real position error can reach the order of 10^-12 meter.