Evaluation method for frequency characteristics of linear actuators in the sub-mu m stroke range using a modified Michelson-type interferometer

摘要

A modified Michelson-type interferometer is used for the evaluation of the frequency characteristics of linear actuators in the sub-mu m stroke range. The vibratory motion of a linear actuator is detected by quadrature signals from the interferometer. The method is based on a previously proposed technique as a method for the evaluation of acceleration pick-ups in international standard (ISO). The scope of measurement is investigated experimentally. The measurable minimum stroke of actuator motion is restricted by the reliability of quadrature signal measurement and is essential at 25 nm. The maximum frequency or velocity of the actuator motion is restricted by the sampling speed of the digital recorder. The maximum velocity of measurement is confirmed up to 1 ms(-1). [References: 7]