1854, Henry Goldbert, a German watchmaker who immigrated to the United States, made the first practical electric lamp in a vacuum glass bottle with a carbonized bamboo wire, which lasted for 400 hours, but he did not apply for a patent in time.
1860, joseph swan, an Englishman, also made a carbon filament lamp, but he failed to obtain a good vacuum environment to make the carbon filament work for a long time.
1878, when the vacuum technology in Britain developed to the required level, he invented a light bulb powered by carbon wire under vacuum and obtained a British patent. Swan's own house is the first private house with electricity lighting in Britain.
1874, two electrical technicians in Canada applied for a patent for electric light: nitrogen was filled under a glass bulb, and carbon rods were electrified to emit light, but they did not have enough financial resources to continue to improve this invention.
1875 sold the patent to Edison. Edison tried to improve the filament after purchasing the patent, and finally made a carbonized bamboo filament lamp that could last for 1200 hours in 1880.
However, after the US Patent Office ruled that Edison invented the carbon filament incandescent lamp, the patent was invalid. After years of litigation, Henry Goebbels won the patent, and finally Edison bought the patent from Goebbels poor widow.
In Britain, Swan accused Edison of patent infringement. Later, they settled out of court and set up a joint venture company in Britain on 1883. Swan later sold his shares and patents to Edison.
At the beginning of the 20th century, carbonized filament was replaced by tungsten filament, and tungsten filament incandescent lamp is still in use today.
1938, the fluorescent lamp was born. 1998 white LED lamp was born.
Extended data:
Edison didn't invent the electric light at first, but he improved it. As early as 180 1 year, a British chemist named humphry davy used platinum wire to electrify and glow in the laboratory.
18 10, he invented the "electric candle" which was illuminated by the arc between two charged carbon rods, which was the earliest prototype of the electric lamp. Joseph swan, another British electrical engineer, after nearly 30 years' research, made a vacuum bulb with electricity and light from carbon wire in 1878+02.
The report about the swan's light bulb gave Edison a great inspiration. 1879 10, Edison finally succeeded in making an incandescent light bulb with carbon fiber as the filament, which is called "carbonized cotton filament incandescent lamp". Later, a large number of incandescent lamps were put into production, and companies were established to establish corresponding power stations, transmission networks and other infrastructure, which soon made electric lamps widely used in the United States.
During this period, he constantly improved his technology, and finally decided to use tungsten wire as the filament, which is called "tungsten lamp" and has been in use ever since, so Edison became a recognized inventor of electric lamp.
References:
Electric light-Baidu encyclopedia