加速度对激光双频干涉仪测量误差的影响

为了减少由于加速度所导致的激光双频干涉仪测量误差,引入二阶多普勒频移,建立了由被测物体加速度所引起的测量误差的理论模型。仿真结果表明,在0.4s时间内0.6g加速度所引起的累积误差可达2.5 nm左右,这对于纳米精度的测量是不应忽视的; 初速度不为零时加速运动会引起更大的误差,而减速运动所引起的误差则相对小。通过实验验证,所测的误差变化趋势与理论模拟比较吻合。

In order to reduce the dual-frequency interferometer measuring error induced by acceleration of measured object, a theoretical model of the interferometry measuring error was put forward by considering second-order Doppler frequency shift. The simulated results show that when muzzle velocity is zero the cumulative error induced by acceleration of 0.6g can be up to 2.5 nm in 0.4 s, which is not negligible in nanometer measurement. Moreover, when muzzle velocity is not zero, the acceleration motion may result in more error and deceleration motion may result in less error. At last, experiments were done to validate the model.