Tail Fiber: Types, Functions, and Common Interfaces

What is Tail Fiber?

A tail fiber, also known as a fiber optic patch cord, consists of a connector on one end and a cut end of the fiber optic cable core on the other. These patch cords are primarily used to connect fiber optic cables to fiber optic transceivers (couplers, jumpers, etc. are also involved).

They are commonly found within fiber optic termination boxes, connecting to other fiber optic cable cores through fusion splicing, simplifying the installation and maintenance tasks of cable systems.

1. Classification of Tail Fibers

Similar to fiber optic jumpers, tail fibers are classified into single-mode and multimode types, differing in color, wavelength, and transmission distances.

Generally, multimode tail fibers are orange, operate at a wavelength of 850nm, and have a transmission distance of around 500m. Single-mode tail fibers are yellow, operating at wavelengths of 1310nm or 1550nm, with longer transmission distances, typically ranging from 10 to 40km.

Additionally, depending on the number of fiber cores, tail fibers can be further classified into single-core, 4-core, 6-core, 8-core, 12-core, 24-core, etc.

2. Functions of Tail Fibers

The primary function of tail fibers is connectivity. By fusing the bare fibers in the optical cable with the tail fiber, a seamless connection is established. The tail fiber has its unique fiber optic head, connecting to the fiber optic transceiver and linking the fiber optic and twisted pair to the information socket.

During the fusion process, essential tools such as fiber optic patch panels, transceivers, tail fibers, couplers, specialized stripping pliers, and fiber optic cutting knives are commonly used. Commonly used interfaces for tail fibers include SC/PC, FC/PC, LC/PC, E2000/APC, ST/PC, and more.

3. Common Types of Tail Fibers

• FC-SC Type: Circular to square tail fiber, where FC connects to ODF boxes, and SC connects to equipment ports. Widely used in early SBS and Optix devices.

• FC-FC Type: Commonly known as circular to circular tail fiber, typically used for jumpers between ODF racks.

• SC-SC Type: Known as square to square tail fiber, often used for interconnecting optical boards between devices.

• SC-LC Type: SC connects to square head tail fiber, belonging to a snap-in connector. Utilized in Huawei OSN series, ZTE S series devices, and earlier Lucent wavelength division equipment.

• LC-LC Type: Primarily used in internal fiber connections between wavelength division devices, though less commonly used.