It is generally believed that the electric light was invented by American Thomas Edison. But if there is serious research, another American, Henry Goebbels (Heinrich G?bel), had invented the same principle and material and a reliable light bulb decades before Edison. Before Edison, many other people also invented the electric light bulb. He has made many contributions to inventions. In 1801, British chemist Davy electrified platinum wire to produce light. He also invented the electric candle in 1810, which used arc lighting between two carbon rods. In 1854, Henry Goebbels used a carbonized bamboo filament and placed it under a vacuum glass bottle to energize it and emit light. His invention today appears to be the first practical incandescent light bulb. The light bulb he tested at that time could last for 400 hours, but he did not immediately apply for a design patent.
In 1850, the Englishman Joseph Wilson Swan began to study electric lights. In 1878, he obtained a British patent for a light bulb powered by carbon filaments under vacuum, and began to establish a company in the United Kingdom to install electric lights in homes.
In 1874, two Canadian electrical technicians applied for an electric light patent. They filled the glass bubble with nitrogen and used an electrified carbon rod to emit light. But they did not have enough financial resources to continue developing the invention, so they sold the patent to Edison in 1875.
After Edison purchased the patent, he tried to improve the filament he used. In 1879, he changed to using carbon filament to make a light bulb, which successfully lasted for 13 hours. By 1880, the carbonized bamboo filament light bulb he created successfully lasted 1,200 hours in the laboratory. But in England, Swann sued Edison for patent infringement and won. Edison's electric light company in England was forced to bring Swann on as a partner. But later Swann sold his rights and patents to Edison. In the United States, Edison's patents were also challenged. The U.S. Patent Office once ruled that his invention had a criminal record and was invalid. Finally, after years of legal battles, Edison obtained the patent for the carbon filament incandescent lamp.
Edison's biggest discovery was the use of tungsten instead of carbon as filament. Then in 1906, General Electric invented a method of making tungsten filament for electric lights. Eventually a cheap method of manufacturing tungsten filament was solved, and tungsten filament light bulbs are still in use today.
The biggest problem with light bulbs is the sublimation of the filament. Because the slight difference in resistance on the tungsten wire causes temperature differences, where the resistance is greater, the temperature rises higher and the tungsten wire sublimates faster, causing a cycle in which the tungsten wire becomes thinner and the resistance further increases; ultimately, the The tungsten wire is burned out. It was later discovered that replacing the vacuum with an inert gas could slow down the sublimation of the tungsten wire. Most light bulbs today are filled with nitrogen, argon, or krypton gas.
Modern incandescent lamps generally have a lifespan of about 1,000 hours.