Connector & Adapter

Fiber Optic Adapters:

Fiber optic adapters (also called couplers) are designed to connect two fiber optic cables together. They come in versions to connect single fibers together (simplex), two fibers together (duplex), or sometimes four fibers together (quad).

Adapters are designed for multimode or singlemode cables. The singlemode adapters offer more precise alignment of the tips of the connectors (ferrules). It is ok to use singlemode adapters to connect multimode cables, but you should not use multimode adapters to connect singlemode cables. This can cause misalignment of the small singlemode fibers and loss of signal strength (attenuation).

When connecting two multimode fibers, you should always make sure they are the same core diameter (50/125 or 62.5/125). A mismatch here will cause attenuation in one direction (where the larger fiber is transmitting light into the smaller fiber).

Fiber optic adapters are typically connecting cables with similiar connectors (SC to SC, LC to LC, etc.). Some adapters, called "hybrid", accept different types of connectors (ST to SC, LC to SC, etc.). When the connectors have differing ferrule sizes (1.25mm to 2.5mm), as found in LC to SC adapters, the adapters are significantly more expensive because of a more complicated design/manufacturing process.

Most adapters are female on both ends, to connect two cables. Some are male-female, which typically plug into a port on a piece of equipment. This then allows the port to accept a different connector than for which it was originally designed. We discourage this use because we find the adapter extending from the equipment is subject to being bumped and breaking. Also, if not properly routed, the weight of the cable and connector hanging from the adapter may cause some misalignment and a degraded signal.[

Fiber Optic Connector:

Whether you are installing a brand new fiber optic network or repairing a legacy system using this fiber optic connector guide will help you determine what kind of connector you are looking at or what type of connector you need to replace.

The List below is a great tool for identifying fiber optic connectors. Use it for reference and even to help you choose the what connectors you should use on your next fiber optic project.

• ST Connector
• FC Connector
• LC Connector
• SC Connector
• MTP Connector
• MU Connector
• D4 Connector
• ESCON Connector
• FDDI Connector
• Biconic Connector
• SMA 905 & 906 Connectors