FC connector

FC connectors are used in datacom, telecommunications, measurement equipment, and single-mode lasers.

[4] The fiber end is embedded in a 2.5 mm ferrule made of zirconia ceramic or stainless steel.

This surface profile means that when the fibers are mated they touch only at their cores, allowing transmission with low loss.

Generally angle-polished connectors have higher insertion loss than good quality straight physical contact ones.

"Ultra" quality connectors may achieve comparable back reflection to an angled connector when connected, but an angled connection maintains low back reflection even when the output end of the fiber is unmated.

Angle-polished connections are distinguished visibly by the use of a green strain relief boot.

PM FC/PC connectors typically use FC/APC keying since the angular alignment tolerance is tighter.