1792 – The first practical optical telecommunication system – Claude Chappe’s semaphore system
French inventor Claude Chappe demonstrated a practical semaphore system that eventually spanned all of France. His system was a series of semaphores mounted on towers, where human operators relayed messages from one tower to the next. It beat hand-carried messages hands down.
1854 – Total internal reflection – the technology foundation for fiber optic communication
One theory slowly took root which would ultimately solve the problem of optical communication. This phenomenon was named total internal reflection.
British physicist John Tyndall demonstrated total internal reflection by guiding light in a jet of water flowing from a tank. In the 1890s, inventors realized that bent quartz rods could carry light, and patented them as dental illuminators.
1880 – Alexander Graham Bell’s optical telephone system
Alexander Graham Bell patented an optical telephone system, which he called the Photophone. He dreamed of sending signals through the air, but the atmosphere didn’t transmit light as reliably as wires carried electricity.
1920 – The patent of using arrays of hollow pipes or transparent rods to transmit images
During the 1920s, John Logie Baird in England and Clarence W. Hansell in the United States patented the idea of using arrays of hollow pipes or transparent rods to transmit images for television or facsimile systems.
1930 – Heinrich Lamm demonstrated image transmission through a bundle of optical fibers
Munich’s medical student Heinrich Lamm was the first person to have demonstrated image transmission through a bundle of optical fibers. In a 1930 paper, he reported transmitting the image of a light bulb filament through a short bundle.
1954 – Van Heel invented fiber cladding
All earlier fibers developed were bare and lacked any form of cladding, with total internal reflection occurring at a glass-air interface.
Dutch scientist Van Heel made the crucial innovation of cladding fiber-optic cables. He covered a bare fiber or glass or plastic with a transparent cladding of lower refractive index. This protected the total reflection surface from contamination and greatly reduced cross talk between fibers.
1960 – The invention of laser
The July 22, 1960 issue of Electronics magazine introduced its report on Theodore Maiman’s demonstration of the first laser.
1964 – The critical and theoretical specification of optical fiber identified by Dr. Charles K. Kao
After a long, hard look at fiber attenuation, Dr. Kao concluded that the high losses of early fibers were due to impurities, not to silica glass itself. He forecasted that fiber loss could be reduced below 20 dB/km for long-range communication devices. Dr. Kao also illustrated the need for a purer form of glass to help reduce light loss.
1970 – Corning Glass’s invention of low loss single mode fiber
Robert Maurer, Donald Keck, and Peter Schultz at Corning Glass announced they had made single-mode fibers with attenuation at the 633-nanometer helium-neon line below 20 dB/km.
1977 – The first live traffic fiber optic system
General Telephone and Electronics tested and deployed the world’s first live telephone traffic through a fiber-optic system running at 6 Mbps.
Soon in May 1977, Bell Lab deployed an optical telephone communication system in the downtown Chicago area, covering a distance of 1.5 miles.
Author: Colin Yao
Article Source: EzineArticles.com
Provided by: Digital Camera Times
- FiOS In Moorestown, NJ
- INMATES AGAINST CRUEL & UNUSUAL PUNISHMENT AT PATUXENT UNSTITUTION
- Get FIOS in Moorestown
Related posts: