Tesla, Nikola (1856–1943)

Croatian-born US physicist and electrical engineer who invented fluorescent lighting, the Tesla induction motor (1882–87), and the Tesla coil, and developed the alternating current (AC) electrical supply system.

The Tesla coil is an air core transformer with the primary and secondary windings tuned in resonance to produce high-frequency, high-voltage electricity. Using this device, Tesla produced an electric spark 40 m/135 ft long in 1899. He also lit more than 200 lamps over a distance of 40 km/25 mi without the use of intervening wires. Gas-filled tubes are readily energized by high-frequency currents and so lights of this type were easily operated within the field of a large Tesla coil. Tesla soon developed all manner of coils which have since found numerous applications in electrical and electronic devices.

Tesla was born in the village of Smiljan in what is now Croatia, of Serbian parents. He emigrated to the USA in 1884, and from 1888 was associated with industrialist George Westinghouse, who bought and successfully exploited Tesla's patents, leading to the introduction of alternating current for power transmission. Tesla neglected to patent many of his discoveries and made little profit from them. Tesla was very interested in the possibility of radio communication and as early as 1897 he demonstrated remote control of two model boats on a pond. He extended this to guided weapons, in particular a remote-control torpedo. In 1900 he began to construct a broadcasting station on Long Island, New York, in the hope of developing ‘World Wireless’, but lost his funding. He also outlined a scheme for detecting ships at sea, which was later developed as radar. One of his most ambitious ideas was to transmit electricity to anywhere in the world without wires by using the Earth itself as an enormous oscillator. In his later years, Tesla grew steadily more paranoid. He would not shake hands for fear of contamination by germs, and he was fearful of spherical surfaces. He spent his time on fantastic projects, like the invention of devices for producing death rays or for photographing thoughts on the retina of the eye. Tesla died of self-inflicted starvation and sleep deprivation: he believed both to be a waste of time and thought that he could substitute them with sessions on a vibrating electrified plate.