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Optical Fiber

Optical Fiber, or Fiber Optics refers to the technology that transmits information such as data, voice, and pictures as light- pulses through glass or plastic fibers In telecommunications.

Fiber optics is the technology that transmits information as pulses of light through strands of fiber optics or plastic over long distances. Optical fibers are about the diameter of a strand of human hair, and when combined into a fiber optic cable, they can carry more data over longer distances and faster than other media. It is this technology that provides homes and businesses with fiber optic internet, phone and television services. A fiber optic cable contains anywhere from a few to hundreds of glass fibers in a plastic sheath. Known as optical cables or fiber optic cables, they carry data signals in the form of light, traveling hundreds of miles much faster than traditional electrical cables.

Fiber Optics

Optical Fiber, or Fiber Optics refers to the technology that transmits information such as data, voice, and pictures as light- pulses through glass or plastic fibers In telecommunications, Optical Fiber virtually replaced copper wire in long-distance telephone, and it links computer through LAN (local area networks).

The basic medium of Fiber Optic Cable is a thin fiber that is typically manufactured from plastic, however most frequently it is made up of glass. A Glass Fiber Optic Cable comes with a diameter of hundred twenty five micrometres (125μm), or 0.125 millimeter (0.005 inch). 

This is the actual diameter of the outer reflective layer that is also called cladding. 

Whereas, the inner transmitting cylinder could have a diameter of 10μm.

A fiber optics cable may contain a variable range of glass fibers, approx a few to hundred. 

Fiber optics cable is commonly used because of its advantages over copper cable. As it provides higher bandwidth and transmit speeds in comparison to that of copper cable.

Optical fibre is truly composed of 2 layers of glass: The core, that carries the particular lightweight signal, and also the protection, which may be a layer of glass encompassing the core. The cladding features a lower index of refraction than the core. That results in Total Internal Reflection within the core. 

Most fibers operate in duplex pairs, one fiber is used to transmit and the different one is used to receive.

Optical fibers are used for long-distance and superior data networking. It is additionally utilized in telecommunication services, for internet, television and telephones.

Working of Optical Fiber

Optical fibers carry data in the form of particles of light, or photons, pulsing through a fiber optic cable. 

The fiber optic core and cladding each have a different refractive index that deflects incoming light at a specific angle. As light signals are sent down the fiber optic cable, they are reflected off the core and cladding in a series of zigzag reflections, following a process called total internal reflection.

Due to the denser glass layers, light signals do not move at the speed of light, but 30% faster than the speed of light. 

In order to renew or amplify the signal throughout its journey, fiber optic transmission sometimes requires repeaters at distant intervals. These repeaters regenerate the optical signal by converting it into an electrical signal, processing that electrical signal, and retransmitting the optical signal. 

Fiber optic cables can now support signals up to 10 Gbps. In general, fiber optic cable becomes more expensive as bandwidth capacity increases.

Types of Optical Fiber

Single-Mode Fiber Cable

Single-mode fiber has the simplest structure. It contains a very thin core and all signals pass straight through the center without bouncing off the edges. 

Single-mode fiber optic cables are typically used in CATV, Internet and telephony applications where they are carried out by single-mode fibers wrapped in a bundle.

Multi-Mode Fiber Cable

Multimode fiber is another type of Fiber Optics Cable. 

It’s about 10 times larger than a single-mode cable. Rays of light can travel through the core following a variety of different paths or in several different modes. 

These types of cables can only carry data over short distances. Therefore, they are used, among other applications, to connect computer networks with each other.

Simplex and Duplex Fiber Cable

Simplex fiber optic cable constructions contain a single strand of glass. Most often, simplex fiber is used when only a single transmit and/or receive line is required between devices, or when a multiplexed data signal (two-way communication over a single fiber) is used. 

A duplex fiber optic cable consists of two strands of glass or plastic. Pre-Terminated Fiber Optic Cable Fiber optic cable on a box-shaped reel with pre-terminated fiber ends. Typically found in a “zip cord” construction format, this cable is most commonly used for full-duplex communications between devices that require separate transmission and reception.

Advantages and Disadvantages

Advantages of Fiber Optic

It supports higher bandwidth capacities. Light can travel farther without having to amplify the signal so much. They are less susceptible to interference, such as electromagnetic interference. They can be submerged in water. Fiber optic cables are stronger, thinner, and lighter than copper cables. They don’t need to be serviced or replaced as often.

Disadvantages of Fiber Optic

Copper cables are usually cheaper than fiber optic cables. Fiber optic requires more protection within an outdoor cable than copper. Installing new cables is labor intensive. Fiber optic cables are usually more fragile. The cable is bent or curved by a radius of a few centimeters.

Conclusion

The Fiber Optic cables are more efficient than that of copper wire so that it is widely used for transmitting the data over the network. Moreover it also provides more bandwidth and speed that makes it so useful for the telecommunication field. Wherever it costs a little bit more than that of copper wire but its so many advantages covers its some of the disadvantages.

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How can we explain an optical fibre in physics?

Ans.  A narrow rod of a glass of very high quality that can transmit signals ...Read full

In telecommunications what benefits can we achieve from using optical fibres?

Ans.  Instead of conducting wires using optical fibres in telecommunications ...Read full

Who is known to be the inventor of optical fibres?

Ans. Charles Kuen Kao is renowned as the father of communication using fibre optics, for discovering specific physic...Read full

What kind of disadvantages does an optical fibre have?

Ans. As optical fibres have advantages, they also have many disadvantages such as optical fibres have a restricted p...Read full

If we use copper wire and optical fibre, which one is better?

Ans. Comparing copper wire and optical fibre, both have their advantages and disadvantages. It depends on our usage ...Read full