Because there are many different types of fiber optic connectors have been developed, we will talk about fiber optic connectors in fairly general terms.
Most popular connectors in use today have some common elements. Let’s examine it below:
The most critical part, fiber is installed, is the ferrule. Ferrule is long, thin cylinder with the fiber mounted in the center hole. The size of the center hole is set to match the cladding of the fiber is usually 125 microns in diameter.
Fiber connector ferrules are made from several types of materials including ceramic (Zirconia), stainless steel and plastic.
The ferrule’s work is the center and align the fiber and protects it from mechanical damage. Finally at the end of the fiber ring and fiber end is polished smooth either flat or curvature.
The ferrule is mounted in the connector body and then the connector body is attached to the fiber optical cable structure. Finally, a strain-relief rubber boot protects the connector cable junction.
Unlike most electronic connectors, fiber optic connectors usually do not have the male-female polarity. Most fiber connectors are male only. Instead, fiber optic connectors to mate in the fiber optic adapter, it is often referred to as mating sleeves or coupling socket. Fiber optic adapter connector types used in different partners such as FC SC connector connector is called hybrid adapters.
Although this method needs to use a separate adapter, fiber optic connector it otherwise to reduce inventory requirements because now you only need to stock a type connector. Another advantage is that fiber optic adapters can be designed to mate one type of connector to another, which is a big plus compared to electronic connectors.
The fiber’s plastic coating is stripped first before the fiber is inserted in the ferrule. The center hole through the ferrule is large enough to fit the fiber cladding (which is usually 125um after fiber coating stripped off) but tight enough to hold the fiber in a fixed position without any further moving.
Standard bore diameters are 126 +1/-0 um for single mode connectors and 127 +2/-0 um for multimode connectors. Because of fiber cladding diameter’s variation from manufacturing, some fiber connector manufacturers also supply a range of ferrule bore sizes such as 124um, 125um, 126um and 127um.
Fiber optic epoxy or adhesive is inkected into the ferrule hole before the fiber is pushed in to hold the fiber in place. The epoxy or adhesive is then cured with high temperature oven according to adhesive manufacturer’s instruction. Finally the fiber end is polished to a smooth face on polishing films.
The ferrule is then slipped inside another hollow cylinder before it is mounted in the connector body. The connector body includes one or more pieces that are assembled to hold the cable and fiber in place. Connector body is made of metal or plastic.
The ferrule end protrudes beyond the connector body so it can slip into the mating sleeves (fiber adapters). A stain relief rubber boot is finally slipped over the cable end of the connector to protect the cable connector junction point.
In fiber optical cross connect boxes or fiber patch panels, an array of connector adpators are mounted inside, ready for you to plug an input fiber cable in one side and an output cable in the other. Fiber connector adapters are also mounted in wall outlets, just like standard phone jacket.