Fiber Optic Wiki

Fiber-Optic Technologies

August 20, 2011

A Brief History of Fiber-Optic Communications—This section discusses the history of fiber optics, from the optical semaphore telegraph to the invention of the first clad glass fiber invented by Abraham Van Heel. Today more than 80 percent of the world's long-distance voice and data traffic is carried over optical-fiber cables.

Modern Conmunication In Modern Society

August 19, 2011

The internet, cell phones, fax machines and pagers are a way of life in modern society. All these technologies rely on lasers and fiber optics. The principle behind a laser lies embedded in the heart of quantum mechanics. Einstein built on the theory of quantum mechanics to explain the photoelectric effect in 1905 and showed that electrons could absorb and emit the energy of photons.

Using Visible Light

August 19, 2011

All forms of modern communication--radio and television signals, telephone conversation, computer data--rely on a carrier signal, a wavelike electromagnetic oscillation with a particular frequency.

Physics In The 20th Century

August 19, 2011

The research that would eventually give rise to the laser had its origins in the branch of physics now known as quantum mechanics. In 1900 Max Planck hypothesized that excited atoms radiate energy in discrete packets, which he called quanta, and not as a continuous range of energies, as the prevailing wave theory of electromagnetic radiation would have it.

Lasers In 20th Century

August 19, 2011

The catch was that amplification by stimulated emission would occur only if more atoms in the population of atoms were in an excited state than in the lower-energy state. That is the opposite of the normal situation, so stimulated emission required what is known as a population inversion--an entire population of atoms had to be artificially boosted into an excited state, usually by exposure to light.

Semiconductor Lasers

August 19, 2011

Transistors make use of the special properties of a class of materials known as semiconductors. Electric current is carried by moving electrons, and ordinary metals, such as copper, are good conductors of electricity because their electrons are not tightly bound to the nucleus of the atom and are freely attracted to a positive charge. Other substances, such as rubber, are insulators--poor conductors of electricity--because their electrons do not move freely.

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