The Difference of Common Fiber Optic Connectors

Fiber optic connectors are often used to link optical fibers where a connect or disconnect capability is needed. The fiber optic connectors come in many configurations and usages, and simplify fiber optic cable installation and maintenance greatly. In function of their connector, fiber optic cables are commonly categorized in LC, SC, FC, ST and MTP/MPO. All these types of connectors can be used with either single mode or multimode fiber optic cables.

- LC (Lucent Connector) is normally held together in a duplex configuration with a plastic clip. The ferrule of an LC connector is 1.25mm. Because of its small dimensions, it is the perfect fit for high-density connections, XFP, SFP, and SFP+ transceivers.

- FC (Ferrule Connector) is a screw type connector with a 2.5mm ferrule. FC is a round shaped threaded fiber optic connector, and it is pretty common choice for example in Video over Fiber Transmission Equipment. However, FC became less popular because of its insertion loss and vibration loosening. At the moment, people tend to use LC and SC instead.

- SC (Subscrber Connector) is a push-pull coupling type of connector and has a 2.5mm diameter.The connector body of an SC connector is square shaped, and two SC connectors are usually held together with a plastic clip (this is referred to as a duplex connection). It is offen used in such equipment like Fiber Multiplexers, GPON and EPON ONU’s, Fiber Media Converters and more.

- ST (Straight Tip) connector was one of the first connector types widely implemented in fiber optic networking applications. ST connections use a 2.5mm ferrule with a round plastic or metal body. Although extremely popular for many years, the ST connector is slowly being supplanted by smaller, denser connections in many installations.

- MTP/MPO fiber connector is a multi-fiber connector which combines fibers from 12 to 24 fibers in a single rectangular ferrule. Because of the high number of fiber strands available in a small connection, MTP/MPO assemblies are used for backbone, cross-connect, and breakout applications.