Development of laser interferometer with picometer resolution using frequency tunable laser

The 6th report Air refractive index fluctuation compensation for displace measuremet

Abstract

Laser interferometer for lenght or displacement measurement widely used in the precision engineering field. A cyclic error and an influence of air refractive index fluctuation are included in the output of a laser interferometer. We have proposed a displacement measurement system which has no cyclic errors and a real-time refractive index change measurement system using tunable lasers. In this report, we will show the result of compensation for displacement measurement using above proposed systems.