The Royal Swedish Academy of Sciences awarded half of this year's Nobel Prize in physics to Charles K. Kao "for groundbreaking achievements concerning the transmission of light in fibers for optical communication", and the other half jointly to Willard S. Boyle and George E. Smith for the invention of the CCD sensor.
The research conducted by the Chinese physicist allowed a rapid development of fiber optic technology. First experiments with rays of light guided by glass fibers were conducted in 1870. Thanks to the phenomenon of total internal reflection the beam was propagated through the fiber, but the transmission was possible only on short distances. This resulted from high attenuation of light waves, reaching up to 100 dB per kilometer (currently, attenuation of modern optical fibers is about 0.2 dB/km).
The situation radically changed in 1966 when Charles Kao published the results of his research and pointed out the cause of so high attenuation. He proved that pollution of the fiberglass with hydroxide ions and ions of elements such as iron, copper and cobalt was the main reason of this phenomenon. The study also proved that another reason of increased attenuation was dissipation of energy occurring in the glass structure due to its inhomogeneity. Thanks to the publication of Ch. Kao, already in 1970 the followers were able to obtain the first pure glass fibers without such contaminants and flaws.
Currently fiber optic networks connect the whole world being the main means of communication and transmission of huge volumes of data between any parts of the worldwide information infrastructure. Nowadays fiber optic installations are competitive in price compared to traditional wiring, and they have far more transmission capacity. It's the reason why they start to reach end users (FTTH - Fiber To The Home).
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