Determining direction of motion during distance measurement - has single interferometer containing mirror with reflection films of different reflectivities and stepped profile

摘要

An arrangement for determining direction of motion during measurement of displacement with an interferometer contains a mirror with at least one additional reflection film with a different degree of reflectivity placed behind a first partially transparent reflection film. The reflection films have at least approximately identical profiles perpendicular to the light incidence direction. The mirror has a stepped profile perpendicular to the light incidence direction. USE/ADVANTAGE - For use with interferometer with light source, fixed and moving mirrors and a light detector. Enables direction of motion to be determined with one interferometer.