Fiber Optic Patch Cords: Types, Characteristics, and Common Interfaces

What is a Fiber Optic Patch Cord?

A fiber optic patch cord, also known as a fiber optic jumper, has connectors on both ends.

A patch cord consists of one or multiple optical fibers of a specific length and optical connectors. It is used to create jump connections from equipment to the fiber optic cabling system and is commonly used to connect optical transceivers and termination boxes.

01 Single-mode Fiber: Typically represented in yellow, with blue connectors and protective sleeves, single-mode patch cords are designed for longer transmission distances. The connection distance for single-mode cables can reach up to 10 kilometers.

02 Multi-mode Fiber: Generally represented in orange (or sometimes gray), with beige or black connectors and protective sleeves, multi-mode patch cords are used for shorter transmission distances. The connection distance for multi-mode cables is much shorter, ranging from 300 meters to 500 meters, depending on the laser type. Multi-mode fibers are cost-effective for applications within buildings or company campuses, while single-mode fibers are more suitable for longer-distance applications. Single-mode fibers can transmit over longer distances but usually require more expensive equipment.

03 Common Fiber Optic Connector Types:

Fiber optic connectors are classified based on the structure of the connector head and include FC, SC, ST, LC, D4, DIN, MU, MT-R, etc. The commonly used types are FC, SC, ST, and LC.

1. FC Interface (Ferrule Connector): Initially used in storage area networks, FC connectors have a metal housing with threaded interfaces, providing secure connections when attached to optical modules.

2. ST Interface (Stab & Twist): Made of metal, ST connectors feature a snap-in interface and are commonly used in fiber optic patch panels.

3. SC Interface (Square Connector): Constructed with plastic, SC connectors use a push-pull mechanism for connection and can latch onto optical modules. They are commonly employed in switches.

   "SC" connectors are standard square-shaped connectors made of engineering plastic, known for their high-temperature resistance and oxidation resistance. SC connectors are generally used on the transmission equipment side.

4. LC Interface (Lucent Connector): Made of plastic, LC connectors are used to connect SFP optical modules. The interface can latch onto optical modules.

   "LC" connectors have a shape similar to SC connectors but are slightly smaller. "FC" connectors have metal heads and are typically used on the ODF side, with metal connectors having a higher number of plug-and-play cycles than plastic connectors. Common labels for tail fiber connectors include "FC/PC," "SC/PC," and others.