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The Electric light is a device that uses electric energy to produce visible light. Until electric light became common in the early 1900's, people could see at night only with candles, fires, gaslights, or oil. During the mid-1800's, a number of inventors tried to create light from electricity. Several lighting pioneers developed incandescent lamps. These lamps operated with batteries and burned out quickly. The widespread use of electric light required not only a lamp, but also a method of distributing cheap electricity to users of the lamp. Thomas Alva Edison developed such a method and became famous as the inventor of the electric light. In 1879, Edison invented his incandescent lamp. It had a filament of carbonised thread. During the early 1880's, he developed one of the first central stations to generate and distribute electricity. Edison's first station, on Pearl Street in New York City, began operating in 1882. During the early 1900's, engineers began to experiment with gaseous-discharge lamps containing mercury. Their work resulted in fluorescent and mercury vapour lamps in the 1930's. Electro luminescence was discovered in 1936. LED's resulted from research on semiconductor devices during the 1960's. In the 1970's, researchers developed energy-conserving light sources, such as metal halide lamps and high-pressure sodium discharge lamps. |
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