Optical jumpers, optical tail fibers and adapters are often used in transmission engineering. FC (commonly known as round head), SC (commonly known as square head) and LC are common. FC is also divided into FC/FC and FC/PC (APC). The former FC is the abbreviation of Ferrule Connector, indicating that its external reinforcement is metal sleeve and fastening is screw; the latter FC indicates that the joint is plane butt, PC is the abbreviation of Physical Connection, indicating that its butt face is physical contact, that is, the end face is convex arch structure, APC and PC type. Similar, but with a special grinding side
PC is spherical, APC is oblique 8 degree spherical, the index is better than PC. At present, FC/PC is commonly used in telecommunication network, and FC/APC is mostly used in cable TV system. Generally written as FC or PC refers to FC/PC optical connector. The shell of SC type is made of cast glass fibre plastics and is in rectangular shape. The plug sleeve (also known as pin) is made of precision ceramics, and the coupling sleeve is made of metal slotted sleeve. Its structure size is the same as FC type. The end face is polished by PC or APC type. The fastening method is plug-and-latch type without rotating head. It is often used in data engineering. The general SC type refers to SC/PC. LC optical fiber connector is made of modular jack (RJ) mechanism. The size of the pin and sleeve used is half that of the ordinary SC, FC and other sizes. LC is commonly used in high density optical interface board of communication equipment. Various optical connectors and their corresponding adapters, also known as flanges, are used on ODF racks for optical fiber connections. FC/PC and SC flanges generally cost about 10-15 yuan per unit. FC/PC fiber hopping (irregular name is double-ended tail fiber), the English name is PATCH CORD, which is a soft fiber with fiber connector at both ends. It is used to connect equipment to ODF rack and jump between ODF rack. The color of light jumper is yellow, indicating single mode jumper. MTRJ-SC fiber hopping, the color of optical hopping line is orange, indicating multi-mode fiber hopping. In addition, there are tail fibers for the end of the cable, the English name is PIGTAIL CORD, one end is fused with the cable, one end is fixed on the ODF. In production, in order to facilitate testing, they are all produced as jumping fibers, that is, both ends have optical fiber connectors. During construction, one jumping fibre becomes two tail fibers when it is cut off from the middle
