1963 Heterostructures Physicist Herbert Kroemer proposes the idea of heterostructures, combinations of more than one semiconductor built in layers that reduce energy requirements for lasers and help them work more efficiently. These heterostructures will later be used in cell phones and other electronic devices. 1966 Landmark paper on optical fiber Charles Kao and George Hockham of Standard Telecommunications Laboratories in England publish a landmark paper demonstrating that optical fiber can transmit laser signals with much reduced loss if the glass strands are pure enough. Researchers immediately focus on ways to purify glass. 1970 Optical fibers that meet purity standards Corning Glass Works scientists Donald Keck, Peter Schultz, and Robert Maurer report the creation of optical fibers that meet the standards set by Kao and Hockham. The purest glass ever made, it is composed of fused silica from the vapor phase and exhibits light loss of less than 20 decibels per kilometer (1 percent of the light remains after traveling 1 kilometer). By 1972 the team creates glass with a loss of 4 decibels per kilometer. Also in 1970, Morton Panish and Izuo Hayashi of Bell Laboratories, along with a group at the Ioffe Physical Institute in Leningrad, demonstrate a semiconductor laser that operates continuously at room temperature. Both breakthroughs will pave the way toward commercialization of fiber optics. 1973 Chemical vapor deposition process John MacChesney and Paul O’Connor at Bell Laboratories develop a modified chemical vapor deposition process that heats chemical vapors and oxygen to form ultratransparent glass that can be mass-produced into low-loss optical fiber. The process still remains the standard for fiber-optic cable manufacturing.
1975 First commercial semiconductor laser Engineers at Laser Diode Labs develop the first commercial semiconductor laser to operate continuously at room temperatures. The continuous-wave operation allows the transmission of telephone conversations. Standard Telephones and Cables in the United Kingdom installs the first fiber-optic link for interoffice communications after a lightning strike damages equipment and knocks out radio transmission used by the police department in Dorset. 1975 First commercial semiconductor laser Engineers at Laser Diode Labs develop the first commercial semiconductor laser to operate continuously at room temperatures. The continuous-wave operation allows the transmission of telephone conversations. Standard Telephones and Cables in the United Kingdom installs the first fiber-optic link for interoffice communications after a lightning strike damages equipment and knocks out radio transmission used by the police department in Dorset. 1977 Telephone companies fiber optic trials Telephone companies begin trials with fiber-optic links carrying live telephone traffic. GTE opens a line between Long Beach and Artesia, California, whose transmitter uses a light-emitting diode. Bell Labs establishes a similar link for the phone system of downtown Chicago, 1.5 miles of underground fiber that connects two switching stations. 1980 Fiber-optic cable links major cities AT&T announces that it will install fiber-optic cable linking major cities between Boston and Washington, D.C. The cable is designed to carry three different wavelengths through graded-index fiber—technology that carries video signals later that year from the Olympic Games in Lake Placid, New York. Two years later MCI announces a similar project using single-mode fiber carrying 400 bits per second. 1987 "Doped" fiber amplifiers David Payne at England’s University of Southampton introduces fiber amplifiers that are "doped" with the element erbium. These new optical amplifiers are able to boost light signals without first having to convert them into electrical signals and then back into light.
1988 First transatlantic fiber-optic cable The first transatlantic fiber-optic cable is installed, using glass fibers so transparent that repeaters (to regenerate and recondition the signal) are needed only about 40 miles apart. The shark-proof TAT-8 is dedicated by science fiction writer Isaac Asimov, who praises "this maiden voyage across the sea on a beam of light." Linking North America and France, the 3,148-mile cable is capable of handling 40,000 telephone calls simultaneously using 1.3-micrometer wavelength lasers and single-mode fiber. The total cost of $361 million is less than $10,000 per circuit; the first transatlantic copper cable in 1956 costs $1 million per circuit to plan and install. 1988 First transatlantic fiber-optic cable The first transatlantic fiber-optic cable is installed, using glass fibers so transparent that repeaters (to regenerate and recondition the signal) are needed only about 40 miles apart. The shark-proof TAT-8 is dedicated by science fiction writer Isaac Asimov, who praises "this maiden voyage across the sea on a beam of light." Linking North America and France, the 3,148-mile cable is capable of handling 40,000 telephone calls simultaneously using 1.3-micrometer wavelength lasers and single-mode fiber. The total cost of $361 million is less than $10,000 per circuit; the first transatlantic copper cable in 1956 costs $1 million per circuit to plan and install. 1991 Optical Amplifiers Emmanuel Desurvire of Bell Laboratories, along with David Payne and P. J. Mears of the University of Southampton, demonstrate optical amplifiers that are built into the fiber-optic cable itself. The all-optic system can carry 100 times more information than cable with electronic amplifiers.
1996 All-optic fiber cable that uses optical amplifiers is laid across the Pacific Ocean TPC-5, an all-optic fiber cable that is the first to use optical amplifiers, is laid in a loop across the Pacific Ocean. It is installed from San Luis Obispo, California, to Guam, Hawaii, and Miyazaki, Japan, and back to the Oregon coast and is capable of handling 320,000 simultaneous telephone calls. |
