Optical Fiber Connectors: An Interlaboratory Comparison of Measurements ofEndface Geometry

摘要

An interlaboratory measurement comparison, dealing with geometrical parameters ofconvex spherical polished optical fiber connector ferrule endfaces, was coordinated by NIST. Most measurements were optical, using interferometric microscopes; a few were mechanical, using stylus profilometers. For radius of curvature, there were small systematic offsets between some participants' data, but these were not much greater than random uncertainties. Whe protrusion/undercut was defined as the distance between the fiber endface and the apex of a sphere fitted to the ferrule endface there were only slight systematic offsets between participants' data, smaller than typical random uncertainties. When protrusion/undercut was defined as the distance between teh fiber endface and a plane fitted to the bore edge of the ferrule endface, however, there were large systematic offsets between data of participants using interferometers from three different manufacturers. Even if these data sets are adjusted to correct for the systematic effects, the measurements spread is larger for the second definition than for the first. For apex offset, systematic offsets were much smaller than random uncertainties. Stylus measurements caused readily observable physical effects on the specimen endfaces.