Optical Links in Fiber Optics

Optical links for data perform three basic functions. First, the data link transmitter converts an electrical input signal to an optical signal. Then, the optical fiber transmits this optical signal. Finally, the data link receiver converts the optical signal back to an electrical signal identical to the original input. However, previous tutorials have not described how optical power transfers from one optical component to another.

Optical links in a system connection may require either a fiber optic splice, connector, or coupler. One type of system connection is a permanent connection made by splicing optical fibers together. A fiber optic splice makes a permanent joint between two fibers or two groups of fibers. There are two types of fiber optic splices-mechanical splices and fusion splices.

Typical fiber optic connectors.

Even though removal of some mechanical splices is possible, they are intended to be permanent. Another type of connection that allows for system reconfiguration is a fiber optic connector. Fiber optic connectors permit easy coupling and uncoupling of optical fibers. Fiber optic connectors sometimes resemble familiar electrical plugs and sockets.

Systems may also divide or combine link signals between fibers. Fiber optic couplers distribute or combine link signals between fibers. Couplers can distribute an optical signal from a single fiber into several fibers. Couplers may also combine optical signals from several fibers into one fiber.

Fiber optic connection losses may affect system performance. Poor fiber end preparation and poor fiber alignment are the main causes of coupling loss. Another source of coupling loss is differences in optical properties between the connected fibers. If the connected fibers have different optical properties,such as different numerical apertures, core and cladding diameters, and refractive index profiles, then coupling losses may increase.

Coupling and Reflection Losses

Fiber Alignment

Fiber End Preparation

Fiber Mismatches

Fiber Optic Splices

Fusion and Multifiber Splices

Fiber Optic Connectors

More Fiberoptic Connectors

Fiber Optic Couplers

More Fiberoptic Couplers

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