Fiber light through thin fibers of glass
Fiber Optics: Their Use in Communications
The field of communications is one in which the technologies are changing on an almost daily basis. Numerous different technologies have been pursued over the past few years; each designed to essentially accomplish several basic purposes in terms of community service. Three of the most actively pursued application include interactive distance learning, video conferencing, and entertainment. While it is the first two, video conferencing and interactive distance learning, which would serve to the best advantage in terms of education and business; it is the last, entertainment which has the most appeal to the largest number of people. The application of various communications applications in terms of education and business is currently being utilized in remote learning programs and company training programs around the nation. One technology has maintained a position close to the lead in terms of staying in the running to win the coveted spot of the worlds most progressive and sought after communications application. This application is that of fiber optics.
To understand fiber optics in its application to communications, one must first have an understanding of the technology itself. The transmission of light through thin fibers of glass or plastic is the basis of the branch of physics known as fiber optics. Capable of transmitting light over more than one-hundred and fifty miles, these fibers are made of either pure glass or plastic. Each fiber is composed of two parts, the core and the cladding. Optical fibers vary in thickness from hair size (0.001 inch) in diameter and up. The core is composed of the glass or plastic and does the actual transmission of data. The core is typically covered in a sheath referred to as cladding.The cladding around each fiber serves to reflect the light traveling through the fiber back inward into the core of the fiber and to prevent the escape of the light out the walls of the fiber.
Light enters one end of the fiber from a light bulb, laser, or some other source, and travels essentially unimpeded all the way to the length of the fiber where it is intercepted by a photosensitive detector such as an electronic device or even the human eye. The distance of travel varies according to the use to anywhere from just a few inches to over one-hundred and fifty miles. Fiber optic cable can transmit large amounts of information over one-hundred and fifty miles almost instantaneously. While it takes five hours to transmit the contents of an encyclopedia over copper wires, the entire work can be transmitted in less than a minute over fiber optics (Yawn PG).
Fibers referred to as single mode are most often used for the longer distance transmissions. Multi mode fibers are used in applications requiring less distance. They are less expensive than single-mode fibers and accept light from a larger variety of sources and from different angles. Single-mode fibers are smaller in diameter than are multi-mode and are particular both about the type of light they will accept and the angle at which it can be introduced. They typically accept light only when it is directly input to the axis of the fiber. This ability requires special light sources such as lasers and special and precise connections both at the light source and to the detector. When several single-mode fibers are connected each connection must also be very precise and exact. All of these requirements of course result in greater costs associated with the use of single mode fibers than would be incurred with the use of multi-mode fibers but that cost is a necessity of long distance transmission.
Optical fibers are used in a countless number of applications. Communication is the most quickly growing field utilizing fiber optics. Optical fibers transmit messages through coded flashes of light which are deciphered at the receiving end. Because they are not subject to electrical interference and have the capability of transmitting huge amounts of data, fiber optic technology is far superior to traditional systems of information transfer using copper cables. Old cable-based systems are rapidly being replaced with fiber optics by communications and entertainment industries. The pace of installation of fiber optic cable has been near-frantic over the last few years with each company seemingly trying to outpace the other. Over the last decade communications and entertainment companies have laid tens of thousands of miles of fiber optic cable in the U.S. In the past year alone, U.S. Signal has spent $9 million installing fiber lines (Hunter PG).
Utilizing the recent improvements in the communication lines makes it possible for us to have unbelievable amounts of information at our fingertips. Great advancement has been made in specialized medical equipment and environmental inspection equipment through the utilization of fiber optics as well (Pietrucha PG). Future possibilities in the field of medicine are particularly promising. Fiberscopes and endoscopes continue to play an increasingly important role in diagnosing illnesses. In addition, fiber optics is now being used to actually treat certain disorders by guiding carefully metered beams of light to affected portions of the body (Cone PG). An even more fascinating application of fiber optics in the field of medicine, however, is the use of fiber optics in performing remote physical exams or diagnoses for patients who otherwise might not be able to travel to see a physician in person.
Home entertainment and communication is another area being heavily impacted by fiber optics. Movies can be piped into our homes at will at any specific time the customer desires. Previously limited to sound only, telephones can now be linked with live video images of each speaker. Cable television companies can offer hundreds of channels all through the new fiber optic hook ups to our homes. With the advent of fiber optics, televisions will become interactive allowing capabilities almost the equivalent of an online computer.
Even for those homes which are not yet wired with fiber optics, the transformation of their living rooms into the media centers of the future isnt that far off. This paper was prepared by writers at The Paper Store… Approximately sixty-five percent of homes presently have traditional copper wire-based cable service. This number is greater, however, for traditional telephone service, up to ninety percent. About eighty percent of U.S. households fall within an 18,000-foot radius of a telephone switching office (Brody PG). The conversion to fiber optics could potentially be almost one-hundred percent complete, however, within just a few years.
With new advances in technology even the remaining copper wire systems can be used to receive large amounts of information over short distances while simultaneously allowing, for example, traditional voice transmissions. Fiber optics can be used to transmit huge amounts of data over long distances to a central point, for example in a subdivision, where it could then be connected to the existing copper wire-based system into the homes of customers. This union of the two technologies would expedite fiber optic connection and capability substantially.
Fiber optics is not only the wave of the future, it is now. Through the use of these revised systems coupled with such features as interactive video (IVOD), viewers will have access to phenomenal amounts of stored data. They will have full control of their programming both in the times they choose to watch it and in how much they watch at a time or how many segments they choose to view more than once or to skip over utilizing fast forward, rewind and pause controls which serve the same function as VCRs. This utilization offers not only enhanced general entertainment features, it also enhances long-distance learning, the integration of data services and voice trunking. For example, software has been developed specifically for the purpose of networking classrooms to facilitate them to simultaneously pull files from the Internet and to enhance the classroom learning experience (Shenoda PG).
As businesses move from Main Street to a global presence, they experience more and more needs in terms of technology. Often times the various fractions of a business are spread across wide geographic areas and coordination between the various offices is easily disjointed. Technological advancements such as the telephone, e-mail, fax, and videoconferencing become the lifelines which connect one unit with the others. These same technological advances come to the rescue of schools and other organizations which could benefit from a networked approach to their activities. Videoconferencing is particularly useful in that it allows the transmission of visual clues which replicate those of traditional face-to-face interactions (Lantz PG). Videoconferencing is an asset to communication and provides a service that no other technology can currently match in terms of the clear transmission of information. This includes both visual images of others involved in the conference and of data such as charts and spreadsheets which are being presented.
Consider the relatively short period of time for which fiber optic technology has been available, it has made a tremendous impact on most aspects of our communications activities. This impact is most definitely not limited to simple voice transmissions. Fiber optic technology allows the integration of such application as interactive video on demand, and teleconferencing applications which have changed the face of the way we do business, pursue our education, and in general with the ways we have available to share information with other people.
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