Fiber optic adhesive connectors LC, SC, FC, ST

Documents

• Description of ST type adhesive optical connector
• Description of SC type adhesive optical connector
• Description of FC type adhesive optical connector
• Description of LC type adhesive optical connector

Optical connectors are used for the production of optical patch cords/pigtails. They are used to terminate optical fiber and cable for subsequent connection to passive or active elements of the optical network. The most commonly used connectors are SC, FC, LC, ST. 

Advantages of LC, SC, FC, ST fiber optic adhesive connectors:

• for the production of optical patch cords/pigtails;
• the most commonly used connectors;
• high quality and reliability.

The SC connector is traditionally used in media converters, optical SFP, GBIC, XENPAK transceivers, network equipment, distribution panels (ODF), and cable television networks. The body cross-section is rectangular. The connector is connected/disconnected by a linear movement along the guides and is fixed with latches. The ceramic ferrule has a cylindrical shape with a diameter of 2.5 mm, and the ferrule end is slightly rounded. The tip is almost completely hidden by the body, so it is less prone to contamination compared to the ST design. The absence of rotating elements ensures safer core pressure. The ceramic tip of the SC connector is decoupled from the connector body and cable sheath, which ensures connection stability in the adapter against vibration and single impacts.

The LC connector is traditionally used in optical transceivers (SFP), some network equipment, as well as in distribution panels where high optical port density is required. LC connectors are a compact version of SC connectors. They also have a rectangular cross-section. The connector is made of plastic and has a latch similar to that used in modular copper cable connectors (RJ-45 type). Therefore, the connection is made in a similar way. The ceramic ferrule has a diameter of 1.25 mm. For different connector types, the body is made of different colored plastic: multimode - beige, single-mode - blue, APC version - green. 

ST-type connectors (from English Straight Tip) are mainly used in measuring instruments, some specialized equipment, and are quite popular in railway networks. The advantage of the connector is the rotary locking mechanism. ST connectors have a simple and reliable design, are easy to install, and relatively inexpensive. The ceramic ferrule is cylindrical with a diameter of 2.5 mm. The ferrule end is slightly rounded. Fixation is carried out by rotating the frame around the axis of the connector, while the base of the connector is fixed (in theory) due to a recess in the connector. The ST connector body is made of nickel-plated brass. ST connectors are available for single-mode and multimode optical fiber with standard tips, for cable with an outer sheath from 2.8 to 3.1 mm, or for 900 μm buffered fiber.

The FC connector is a fairly common type of optical connector in telecommunications networks, cable television networks, and specialized systems. It is also used in measuring equipment. The advantage of the connector is the threaded connection, which provides a good connection. The connector body is made of nickel-plated brass. For fixation in the adapter, the FC connector is equipped with an M8*0.75 threaded nut. The spring-loaded ceramic ferrule of the connector is completely decoupled from the connector body and cable sheath, which guarantees high mechanical reliability of the connection.