Design and construction of six-degree-of-freedom motion error measurement system in a linear stage using angle sensor-combined grating interferometry

摘要

The measurement method of a six-DOF motion error in an ultraprecision linear stage based on grating interferometry is presented. It consists of a diffractive optical element as a grating scale, a corner cube, four separate two-dimensional position sensitive detectors, four photodiodes and auxiliary optics components. With a single traversal of the stage along X direction, the optical sensor measured the motion in high resolution along each axis: less than 0.03 arcsec, 20 nm, and 0.4 mn for the rotational, Y and Z directions, and X direction, respectively. A laser interferometer and autocollimator were used for comparison. As a result, the motion errors were successfully measured and the frequency response of those signals was analysed through a fast Fourier transform.