Fiber optical connectors

Fiber optical connectors are used to join optical fibers where a connect/disconnect capability is required. There are many types of connectors, the commonly types are LC, SC, FC, ST, MU, E2000.

LC is Lucent Connect or Little Connector or Local Connector. Its ferrule diameter is 1.25mm based on standard of IEC 61754-20. They are often found on small form-factor pluggable transceivers.

SC is Subscriber Connector or square connector or standard connector. Its ferrule diameter is 2.5mm and based on the standard of IEC 61754-4. SC connectors offer excellent packing density and their push-pull design reduces the chance of fiber end face contact damage during connection; frequently found on the previous generation of corporate networking gear, using GBICs.

FC’s long form is ferrule connector or fiber channel. FC connector has same ferrule diameter as SC but standard (IEC-61754-13). FC connectors need to be mated more carefully than the push-pull types due to the need to align the key, and due to the risk of scratching the fiber end face while inserting the ferrule into the jack. FC connectors have been replaced in many applications by SC and LC connectors.

ST’s long form is straight tip. The ferrule diameter is 2.5mm and according to standard IEC 61754-2. ST has a key which prevents rotation of the ceramic ferrule, and a bayonet lock similar to a BNC shell.

MU means miniature unit, 1.25mm of ferrule diameter and IEC 61754-6. It is common in Japan.

E2000 meets a criterion of IEC 61754-15, typical apply in telecom and DWDM systems.