Spherical interferometry for the characterization of precision spheres. (25th August 2016)

• Record Type: Journal Article
• Authors: Nicolaus, R A; Bartl, G
• Is Part Of: Surface topography. Volume 4:Number 3(2016:Jul./Sep.)
• Publication Date: 2016-08-25
• Subjects: spherical interferometry -- surface -- silicon sphere -- Avogadro's constant; Surfaces (Physics) -- Periodicals; Surfaces (Physics) -- Measurement -- Periodicals; 530.417
• DOI: 10.1088/2051-672X/4/3/034007
• Languages: English
• ISSNs: 2051-672X

Abstract

Abstract: Interferometry with spherical wavefronts is usually used for characterizing precise optics. A special spherical interferometer was set up to measure the volume of high precision spheres used for the new definition of the SI unit kilogram, for which a fundamental constant, such as Planck's constant h or Avogadro's constant N A, was to be determined. Furthermore with this type of interferometer and with a special evaluating algorithm, absolute form deviations of spheres can be determined. With this knowledge, a sphere can be processed further to reach unrivaled small sphericity deviations.