Compensation of non-harmonic cycle error of interferometer encoders in the system.

摘要

Method, after the first beam is diffracted by the encoder scale, to obtain an interference signal based on a combination of the first beam and the reference beam from the detector of the interferometer system, to correct the interference signals, the non-harmonic wave period obtaining an error compensation signal based on the error by the electronic processor, based on the interference signal and the error compensation signal, and includes outputting the information on the change in position of the encoder scale relative to the optical assembly of the interferometer system.