The Radius of Curvature (ROC) refers to the curvature of the connector's ferrule end-face. A well-defined. The Telcordia GR-326 standard document sets forth the Telcordia view of the technical generic requirements for, and characteristics required of, connectors used for joining single-mode optical fibers, and for the jumper assemblies made using such connectors”. Con-sequently, these connectors are used wherever frequ-ent configuration as well as me suring tests are neces-sary. To begin with, Insertion Loss (IL) and Re-turn Loss (RL) are crucial. Standards such as TIA-455-218 (FOTP-218), IEC 61300-3-16, IEC 61300-3-17 and IEC 61300-3-23 describe how to measure the three-dimensional properties of a single fiber optic connector endface. The three main properties measured are: The first step given in these standards is to obtain a. Thorlabs' Vytran® Connect-Chek® Interferometer automatically and precisely measures radius of curvature, apex offset of polish, and fiber undercut or protrusion on any PC or APC, single-fiber connector. The CC6000 interferometer uses a non-contact tilted-phase-analysis technique for fast, reliable. The geometry of the end face or tip of fiber optic termini is a key factor connector.