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The first light bulb was created by British inventor Joseph Wilson Swan in 1860, who used carbonised paper filaments in an evacuated glass bulb to create light. Unfortunetly, the light bulb was inefficient and did not have a good life span. Swan created a carbon bulb with a longer life in 1875.

In 1874, two Canadians - Henry Woodward and Mathew Evans patented the an electric light bulb. They later sold the patent to Thomas Edison for $5,000.

Alexander Nikolayevich Lodygin independently developed an incandescent light bulb in 1874. Many others also had a hand in the development of a practical device for the production of electric light.

In 1801 Sir Humphry Davy, an English physician, made platinum strips glow by passing an electric current through them, but the strips evaporated too quickly to make a useful light source. The problem of the filament burning out after a few minutes, and the low resistance and high current draw made incandescent lamps a failure in practical terms until the developments by Edison and Swan in the 1870's. ^[1] In 1809 Davy created the first arc lamp by creating a small but blinding electrical connection between two charcoal rods connected to a battery. Demonstrated to the Royal Institution of Great Britain in 1810, the invention came to be known as the Arc lamp.

In 1835 James Bowman Lindsay demonstrated a constant electric light at a public meeting in Dundee, Scotland. He stated that he could "read a book at a distance of one and a half feet". However, having perfected the device to his own satisfaction, he turned to the problem of wireless telegraphy and did not develop the electric light any further. His claims are not well documented.

In 1840, a British scientist Warren de la Rue enclosed a platinum coil in a vacuum tube and passed an electric current through it. The design was based on the concept that the high melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain less gas molecules to react with the platinum, improving its longevity. Although it was an efficient design, the cost of the platinum made it impractical for commercial use.

In 1841 Frederick de Moleyns of England was granted the first patent for an incandescent lamp, with a design using powdered charcoal heated between two platinum wires contained within a vacuum bulb.

In 1845 American John William Starr acquired a patent for his own incandescent light bulb involving the use of carbon filaments.^[2] He died shortly after obtaining the patent. Aside from the information contained in the patent itself, little else is known about him.

In 1851 Robert Houdin publicly demonstrated incandescent light bulbs on his estate in Blois, France. His light bulbs are on permanent display in the museum of the Chateau of Blois.

In 1872 Alexander Nikolayevich Lodygin invented an incandescent light bulb. In 1874 he got a patent for his invention .

In 1893, the German inventor Heinrich Göbel claimed he had developed the first light bulb in 1854: a carbonized bamboo filament, in a vacuum bottle to prevent oxidation, and that in the following five years he developed what many call the first practical light bulb. In a patent interference suit in 1893, the judge ruled that his claim was "extremely improbable."

Joseph Wilson Swan (1828–1914) was a physicist and chemist born in Sunderland, England. In 1850 he began working with carbonized paper filaments in an evacuated glass bulb. By 1860 he was able to demonstrate a working device but the lack of a good vacuum and an adequate supply of electricity resulted in a short lifetime for the bulb and an inefficient source of light. By the mid-1870s better pumps became available, and Swan returned to his experiments. Swan received a British patent for his device in 1878. Swan reported success to the Newcastle Chemical Society, and at a lecture in Newcastle in February 1873 he demonstrated a working lamp that utilized a carbon fiber filament, but by 1877 he had turned to slender rods of carbon. The most significant feature of Swan's lamp was that there was little residual oxygen in the vacuum tube to ignite the filament, thus allowing the filament to glow almost white-hot without catching fire. From this year he began installing light bulbs in homes and landmarks in England, and by the early 1880s he had started his own company.

Across the Atlantic, parallel developments were also taking place. On July 24, 1874 a Canadian patent was filed for the Woodward and Evans Light by a Toronto medical electrician named Henry Woodward and a colleague Mathew Evans. They built their lamps with different sizes and shapes of carbon filaments held between electrodes in glass globes filled with nitrogen. Woodward and Evans attempted to commercialize their bulb, but were unsuccessful. Nonetheless, Thomas Edison considered their approach sufficiently promising that he bought the rights to both their Canadian and US patents for $5000USD before embarking on his own light bulb development program.

After many experiments with platinum and other metal filaments, Edison returned to a carbon filament (the first successful test was on October 21, 1879; it lasted 13.5 hours). Edison continued to improve this design and by 1880 had the patent for a lamp that could last over 1200 hours using a carbonized bamboo filament. Edison and his team did not find this commercially viable filament until more than 6 months after Edison filed the patent application.

In January 1882, Lewis Latimer received a patent for the "Process of Manufacturing Carbons", an improved method for the production of light bulb filaments which was purchased by the United States Electric Light Company.

In Britain, the Edison and Swan companies merged into the Edison and Swan United Electric Company (later known as Ediswan, which was then incorporated into Thorn Lighting Ltd). Edison was initially against this combination, but was eventually forced to cooperate, and the merger was made. Eventually, Edison acquired all of Swan's interest in the company. Swan sold his United States patent rights to the Brush Electric Company in June 1882. Swan later wrote that Edison had a greater claim to the light than he, in order to protect Edison's patents from claims against them in the US.

U.S. Patent 0223898  by Thomas Edison for an improved electric lamp, January 27, 1880

The United States Patent Office gave a ruling October 8, 1883 that Edison's patents were based on the prior art of William Sawyer and were invalid. Litigation continued for a number of years. Eventually on October 6, 1889, a judge ruled that Edison's electric light improvement claim for "a filament of carbon of high resistance" was valid.

In addressing the question "Who invented the incandescent lamp?" historians Robert Friedel and Paul Israel (1987, 115-117) list 22 inventors of incandescent lamps prior to Swan and Edison. They conclude that Edison's version was able to outstrip the others because of a combination of factors: an effective incandescent material, a higher vacuum than others were able to achieve and a high resistance lamp that made power distribution from a centralized source economically viable. Another historian, Thomas Hughes, has attributed Edison's success to the fact that he invented an entire, integrated system of electric lighting. "The lamp was a small component in his system of electric lighting, and no more critical to its effective functioning than the Edison Jumbo generator, the Edison main and feeder, and the parallel-distribution system. Other inventors with generators and incandescent lamps, and with comparable ingenuity and excellence, have long been forgotten because their creators did not preside over their introduction in a system of lighting." (Hughes 1977, 9)

In the 1890s, the Austrian inventor Carl Auer von Welsbach worked on metal-filament mantles, first with platinum wiring, and then osmium, and produced an operative version in 1898.

In 1897, German physicist and chemist Walther Nernst developed the Nernst lamp, a form of incandescent lamp that used a ceramic globar and did not require enclosure in a vacuum or inert gas. Twice as efficient as carbon filament lamps, Nernst lamps were briefly popular until overtaken by lamps using metal filaments.

In 1903, Willis Whitnew invented a filament that would not blacken the inside of a light bulb. (Some of Edison's experiments to stop this blackening led to the invention of the electronic vacuum tube.) It was a metal-coated carbon filament. In 1906, the General Electric Company was the first to patent a method of making tungsten filaments for use in incandescent light bulbs. The filaments were costly, but by 1910 William David Coolidge (1873–1975) had invented an improved method of making tungsten filaments. The tungsten filament outlasted all other types of filaments and Coolidge made the costs practical.

Operation

Incandescent light bulbs consist of a glass enclosure (the "envelope, or bulb") which either contains a vacuum or is filled with a low-pressure noble gas. Irving Langmuir found that filling the bulb with an inert gas reduces evaporation of the filament and reduces the required strength of the glass. Inside of the bulb is a filament of tungsten wire, through which an electrical current is passed. The current heats the filament to an extremely high temperature (typically 2000 to 6000 K depending on the filament type, shape, and amount of current passed through). Heated electrons in the continuous energy bands of tungsten become excited and then transition to lower energy states of the solid. As they do, they release thermally equilibrated photons which have a black body spectrum. This spectrum, unlike those caused by non-equilibrium atomic or molecular transitions such as in a mercury-vapor lamp, is continuous, typically peaking in the visible light but also containing significant energy in the near-infrared wavelengths.

Incandescent light bulbs usually also contain a glass mount on the inside, which supports the filament and allows the electrical contacts to run through the envelope without gas/air leaks. Many arrangements of electrical contacts are used, such as a screw base (one or more contacts at the tip, one at the shell), a bayonet base (one or more contacts on the base, shell used as a contact or only used as a mechanical support), and for some lamps an electrical contact at either end of a tubular lamp. Contacts in the lamp socket allow the electrical current to pass through the filament. Power ratings range from about 0.1 watt to about 10,000 watts, and up. To improve the efficacy of the lamp, the filament usually consists of coils of fine wire, also known as a 'coiled coil'. For a 60 watt 120-volt lamp, the length of the filament is usually 6.5 feet or 2 metres.

One of the smallest problems of the standard electric light bulb is evaporation of the filament. The largest problem is the inevitable variations in resistivity along the filament cause non-uniform heating, with "hot spots" forming at points of higher resistivity. Thinning by evaporation increases resistivity. But hot spots evaporate faster, increasing their resistivity faster—a positive feedback which ends in the familiar tiny gap in an otherwise healthy-looking filament. Irving Langmuir suggested that an inert gas, instead of vacuum, would retard evaporation and still avoid combustion, and so ordinary incandescent light bulbs are now filled with nitrogen, argon, or krypton. However, a filament breaking in a gas-filled bulb can pull an electric arc, which may spread between the terminals and cause very heavy current flow; intentionally thin lead-in wires or more elaborate protection devices are therefore often used as fuses built into the light bulb.

During ordinary operation, the tungsten of the filament evaporates; hotter, more-efficient filaments evaporate faster. Because of this, the lifetime of a filament lamp is a trade-off between efficiency and longevity. The trade-off is typically set to provide a lifetime of 750-1000 hours for ordinary lamps. 

In a conventional (not halogen) lamp, the evaporated tungsten eventually condenses on the inner surface of the glass envelope, darkening it. For bulbs that contain a vacuum, the darkening is uniform across the entire surface of the envelope. When a filling of inert gas is used, the evaporated tungsten is carried in the thermal convection currents of the gas, depositing preferentially on the uppermost part of the envelope and blackening just that portion of the envelope.

Some old, high-powered lamps used in theatre, projection, searchlight, and lighthouse service with heavy, sturdy filaments contained loose tungsten powder within the envelope. From time to time, the operator would remove the bulb and shake it, allowing the tungsten powder to scrub off most of the tungsten that had condensed on the interior of the envelope, removing the blackening and brightening the lamp again.

When a light bulb envelope breaks while the lamp is on or if air leaks into the envelope, the hot tungsten filament reacts with the air, yielding an aerosol of brown tungsten nitride, brown tungsten dioxide, blue-violet tungsten pentoxide, and yellow tungsten trioxide which then deposits on the nearby surfaces or the bulb interior.

Glass bulb (or "envelope") Low pressure inert gas Tungsten filament Contact wire (goes to foot) Contact wire (goes to base) Support wires Glass mount/support Base contact wire Screw threads Insulation Electrical contact