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BeskrivelseTesla-bulb.jpg
English: Serbian-American inventor Nikola Tesla demonstrating wireless power transmission, probably in his New York laboratory in the 1890s. The bulb is a prototype "fluorescent" light he invented consisting of a partially evacuated glass bulb with a single metal electrode. Nearby but not visible there is one of his Tesla coil high voltage oscillators which produces a radio frequency electric field. The electric field ionizes the gas in the bulb, causing it to glow similar to a neon light. Tesla invented a residential wireless lighting system in the 1889s.
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