The earliest practical electric lamp is the incandescent lamp. However, long before the advent of the incandescent lamp, Humphry Davy, an Englishman, made arc lamps with 2000 batteries and two carbon sticks. However, such arc lamps are too bright and produce too much heat and are not durable, so they cannot be used in ordinary places.
In 1854, Henry Gerber, a German watchmaker who immigrated to the United States, made the first functional electric light from a carbonized bamboo stick placed in a vacuum glass bottle. It lasted for 400 hours, but he did not apply for a patent soon enough. In 1860, The Englishman Joseph Swan also made a carbon filament electric lamp, but he could not get a good vacuum environment to keep the carbon filament working for a long time. It wasn't until 1878, when British vacuum technology was up to snug, that he invented a light bulb powered by carbon wire in a vacuum and received a British patent. Mr. Swan's own house was the first private home in Britain to be electrified.
In 1874, two Canadian electricians applied for a patent for a light bulb that would glow with an electrified carbon rod by filling it with nitrogen gas under a glass bubble, but they could not afford to continue perfecting the invention and sold the patent to Edison in 1875.Edison bought patents and tried to improve the filament, eventually producing a carbonized bamboo lamp that would last 1,200 hours in 1880.
However, the United States Patent Office ruled that Edison's invention of the carbon filament incandescent lamp lag behind others and the patent was invalid. After years of legal battles, Henry Goebbels won the patent, and Edison eventually bought it from Goebbels's impoverished widow. In England, Swann sued Edison for patent infringement, and they settled out of court to set up a joint company in England in 1883.Swan later sold his shares and patents to Edison.
At the beginning of the 20th century, carbide filaments were replaced by tungsten wires, which are still used today.
In 1938, fluorescent lamps were introduced. In 1998 white LED lights were born.
Now along with the more fast development upon the technologies, there are more and more new and innovative products coming out. They’re more smart and small in size but with more technologies integrated. They can be portable, easy installation, no need wiring.
Before the lighting needs to be powered by city grid, the color is simply white. Now the lights can be powered by different sizes and shapes of solar panels. The lights can be made out in different shapes with different functions. They can be simple white, red, blue, and yellow and so on. And they also can be RGB.
The lights now are not only the lighting tools, but the house, city, park, road indispensable decorative products.
How to evaluate if the city is prosperous? Pls try to visit them at night. The ones, shining with most gorgeous lights must be very lively, but also the most popular city. There are more beautiful lights for your option. There are always one for you. Try to find more here.