16-02-2013, 02:24 PM
SEMINAR ON FIBER USED IN ADVANCE COMMUNICATION
FIBER USED IN ADVANCE.docx (Size: 27.44 KB / Downloads: 21)
ABSTRACT
Optical communication systems date back to the 1790s, to the optical semaphore telegraph invented by French inventor Claude Chappe.
In 1880, Alexander Graham Bell patented an optical telephone system, which he called the Photophone.
By 1970 Corning Glass invented fiber-optic wire or "optical waveguide fibers" which was capable of carrying 65,000 times more information than copper wire.
Corning Glass developed with loss of 17 dB/km at 633 nm by doping titanium into the fiber core.
By June of 1972, multimode germanium-doped fiber had developed with a loss of 4 dB per kilometer and much greater strength than titanium-doped fiber.
Prof. Kao was awarded half of the 2009 Nobel Prize in Physics for "groundbreaking achievements concerning the transmission of light in fibers for optical communication".
Today more than 80 percent of the world's long-distance voice and data traffic is carried over optical-fiber cables