An optical fiber or fibre is a thin, transparent fiber, usually made of glass or plastic, for transmitting light. Fiber optics is the branch of applied science and engineering concerned with such optical fibers.

Optical fibers are commonly used in telecommunication systems, as well as in illumination, sensors, and imaging optics.

Principle of operation

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An optical fiber (American spelling) or fibre (British spelling) is a cylindrical dielectric waveguide that transmits light along its axis, by the process of total internal reflection. The fiber consists of a denser core surrounded by a cladding layer. For total internal reflection to confine the optical signal in the core, the refractive index of the core must be greater than that of the cladding. The boundary between the core and cladding may either be abrupt, in step-index fiber, or gradual, in graded-index fiber.

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The Economist: Telecommunications

Alcatel-Lucent:
Thu, 31 Jul 2008 12:10:21 -0000
The architects of a big telecoms-equipment merger decide to hang upWHEN Alcatel, a French maker of telecoms equipment, announced its plan in 2006 to merge with Lucent, an American rival, reactions were mixed. There was general agreement that bigger was better and that the combined firm would benefit from greater geographical reach. But there was also scepticism that its French and American managers would be able to get along. With good reason, it seems: on July 29th Alcatel-Lucent announced its sixth consecutive quarterly loss and the resignations of Serge Tchuruk, its French chairman, and Patricia Russo, its American chief executive. Their firm’s troubles stem in large part from its internal clash of cultures.This clash was an unhelpful distraction, given that the entire telecoms-equipment industry is suffering. The bonanza of 2000-05, when European operators upgraded their mobile-phone networks to new “third-generation” (3G) technology, is winding down. Sales growth is slowing, and even Ericsson, the industry leader, has seen its share price fall by 50% in the past year. Margins have also been squeezed by the rise of Huawei and ZTE, two Chinese firms. Their prices are sometimes 40-50% lower than those of Western vendors. ...
Tech.view:
Fri, 25 Jul 2008 07:24:51 -0000
Telecommuters need more than e-mail and a broadband connectionTHE best thing about being a foreign correspondent is not having to commute to the office every day, attend dreary meetings, dress soberly, and generally get distracted from the nitty-gritty of doing the job. The worse thing is being out of touch with colleagues at head office, with little say over how your stories are treated. But if you can handle the patchy feedback and total lack of control, the freedom pays dividends in productivity and sheer job satisfaction.Being one of the most portable jobs on the planet, journalism provides a daily reminder that work is something you do, not some place you go to. For the past quarter of a century, your correspondent has smirked about the time and energy he’s saved through not having to travel to work. ...
Telecoms in Mexico:
Thu, 10 Jul 2008 13:30:55 -0000
More competition should help to drive down exorbitant phone chargesIT HAS become quaint, in the era of Skype and unlimited calling plans, to worry too much about the cost of phone calls. But it is a textbook case of the old saying: “Them as has, gets”. The well-connected executive can use any number of voice-over-internet services to make free calls; but the rural poor, if they have phones at all, must pay high rates. Perhaps nowhere is this more true than in Mexico, where Carlos Slim, by some estimates the world’s richest man, dominates the telecoms industry. He controls Telmex, which has 81% of the fixed-line market, and Telcel, which has 72% of the mobile market. In the first quarter of 2008 Telmex had a profit margin before interest, taxes, depreciation and amortisation of 48.7%; for Telcel the figure was 52.1%.This is well above the global average for telecoms firms of 35%, says Martin Lara, an analyst at Vector Casa de Bolsa, a research firm. Base tariffs have fallen in Mexico in recent years, but they do not include things like international calls or calls to mobile phones. Competition has not helped much, because smaller firms have been reluctant to undercut Mr Slim’s companies by very much—and high prices boost their profits, too. “No one wants to destroy these profits overnight,” says Mr Lara. ...
Telemedicine:
Thu, 05 Jun 2008 14:04:15 -0000
Medicine: Telemedicine permits remote consultations by video link and even remote surgery, but its future may lie closer to home FEW places on earth are as isolated as Tristan da Cunha. This small huddle of volcanic islands, with a population of just 269, sits in the middle of the South Atlantic, 1,750 miles from South Africa and 2,088 miles from South America, making it the most remote settlement in the world. So it is a bad place to fall ill with an unusual disease, or suffer a serious injury. Because the islands do not have an airstrip, there is no way to evacuate a patient for emergency medical treatment, says Carel Van der Merwe, the settlement’s only doctor. “The only physical contact with the outside world is a six to seven day ocean voyage,” he says. “So whatever needs to be done, needs to be done here.”Nevertheless, the islanders have access to some of the most advanced medical facilities in the world, thanks to Project Tristan, an elaborate experiment in telemedicine. This field, which combines telecommunications and medicine, is changing as technology improves. To start with, it sought to help doctors and medical staff exchange information, for example by sending X-rays in electronic form to a specialist. That sort of thing is becoming increasingly common. “What we are starting to see now is a patient-doctor model,” says Richard Bakalar, chief medical officer at IBM, a computer giant that is one of the companies in Project Tristan. ...
Telecoms in China:
Thu, 29 May 2008 13:41:52 -0000
The long-awaited reorganisation of China's vast telecoms industry beginsBY ANY measure—revenues, employees, customers—it is the largest industrial reorganisation ever. And, reflecting how business is done in China, it was announced in the most modest way, with a posting on a government website on May 24th. The country's telecoms industry, with nearly 600m mobile subscribers, 360m fixed-line customers and $244 billion in revenue, will be reconfigured. Six companies will be collapsed into three, each spanning mobile, fixed and broadband services.China Mobile, the world's largest mobile operator by subscribers, will merge with China TieTong, the smallest fixed-line operator. China Telecom, the country's biggest fixed-line operator, will acquire one of the mobile networks run by China Unicom, which will merge its remaining mobile operations with China Netcom, another fixed-line operator. A sixth operator, China Satcom, will be taken over by China Telecom. ...
Telecoms infrastructure:
Thu, 22 May 2008 12:52:34 -0000
A new boom in cable-laying—but this time it is rationalEVEN as data centres pop up all over the globe to support “cloud computing”, another construction boom is taking place below the waves. After years without much investment in undersea fibre-optic cables, dozens of new cables will be constructed over the next three years, at a total cost of about $7.1 billion, according to TeleGeography, a market-research firm (see chart). And this is likely to be an underestimate, since other projects are being planned.You may be thinking: will they never learn? This new investment boom comes only a few years after a spectacular telecoms crash. In the late 1990s internet gurus convinced financial markets that worldwide data-traffic would double every 100 days; this led them to bet billions building global fibre-optic networks. In 2001 alone, network operators such as Global Crossing spent nearly $13.5 billion laying undersea cables. But when the deluge of traffic failed to materialise, the boom swiftly turned to bust. ...

BBC News | Business | World Edition

US GDP rebounds with 3.3% growth
Thu, 28 Aug 2008 14:50:50 -0000
The US economy grew 3.3% in the second quarter of 2008, the Commerce Department said, much higher than first thought.
Dell pricing policy hits profits
Thu, 28 Aug 2008 21:25:40 -0000
Dell says that a "strategic" effort to cut the prices of its computers, had dented its earnings.
Zoom Airlines suspend all flights
Thu, 28 Aug 2008 20:09:50 -0000
Transatlantic budget carrier Zoom Airlines suspends all operations after applying to go into administration.

NYT > World Business

Even Toyota Trims Goal in Shift From Big Vehicles
Fri, 29 Aug 2008 01:17:09 -0000
The automaker cut its sales forecasts, warning that higher fuel costs and a slowdown in the United States and Europe would probably hold back the auto business at least through 2009.
Report Accuses Officials In China of Embezzlement
Fri, 29 Aug 2008 00:32:33 -0000
A report from China’s top auditor says that ten central government departments “misused or embezzled” more than $660 million last year.
Canadian Airline Shuts, Stranding Hundreds of Passengers
Fri, 29 Aug 2008 01:18:53 -0000
Hundreds of travelers, including many in Europe, were stranded after Zoom Airlines, based in Ottawa, abruptly stopped operations and sought protection from creditors.

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