History of Light Bulbs Timeline

On 4 March 1880, just five months after Edison's light bulb, Alessandro Cruto developed a process to create thin carbon filaments by heating thin platinum filaments in gaseous ethyl alcohol to coat them with pure graphite, then sublimating the platinum at high temperatures.

Image source: Alessandro Cruto

In 1882 at the Munich Electrical Exhibition in Bavaria, Germany, Alessandro Cruto demonstrated bulbs that were more efficient than Edison's and produced a better, whiter light.

On 17 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.

Image source: Lewis Howard Latimer

Around 1893, Italian inventor Arturo Malignani discovered that phosphorus vapours could chemically bind remaining water and oxygen inside bulbs. In 1896 he patented a process introducing red phosphorus as a getter, allowing economic bulbs lasting 800 hours; Edison acquired his patent in 1898.

Image source: Incandescent light bulb

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.

Image source: Nernst lamp

US patent 575002A, issued on 1 December 1897 to Alexander Lodygin, describes filaments made of rare metals, among them tungsten, foreshadowing the metal filaments that would dominate the industry.

From 1898 to around 1905, osmium was used as a filament in lamps made by Carl Auer von Welsbach, part of the shift from carbon to metal filaments that began displacing carbon around 1904.

Image source: Carl Auer von Welsbach

In 1902, Siemens developed a tantalum lamp filament that was more efficient than graphitized carbon filaments since they could operate at higher temperature. General Electric bought the rights and produced tantalum filament lamps in the US until 1913.

Image source: Tantalum

On 13 December 1904, Hungarian Sándor Just and Croatian Franjo Hanaman were granted a Hungarian patent for a tungsten filament lamp. Tungsten filament lamps were first marketed by the Hungarian company Tungsram in 1904.

Image source: Tungsram

By 1910, a process was developed by William D. Coolidge for ductile tungsten, and by 1911 General Electric had begun selling incandescent light bulbs with ductile tungsten wire, greatly improving durability and efficiency.

Image source: William D. Coolidge

In 1913, Irving Langmuir found that filling a lamp with inert gas (nitrogen at first, and later argon) instead of a vacuum resulted in twice the luminous efficacy and reduced bulb blackening. He patented his device on April 18, 1916.

Image source: Irving Langmuir

In 1917, Burnie Lee Benbow was granted a patent for the coiled coil filament, in which a coiled filament is then itself wrapped into a coil by use of a mandrel, improving efficiency further.

In 1921, Junichi Miura created the first double-coil bulb using a coiled coil tungsten filament while working for Hakunetsusha, a predecessor of Toshiba. The company developed mass production of coiled coil filaments by 1936.

Image source: Toshiba

In 1930, Hungarian Imre Bródy filled lamps with krypton gas rather than argon and designed a process to obtain krypton from air. Production of krypton-filled lamps began at Ajka, Hungary in 1937, in a factory co-designed by Polányi and Egon Orowan.

Image source: Imre Bródy

The Centennial Light is accepted by the Guinness Book of World Records as having been burning almost continuously at a fire station in Livermore, California, since 1901, making it the longest-lived light bulb known.

Image source: Centennial Light

A 40-watt bulb in Texas has been illuminated since 21 September 1908. It once resided in an opera house where notable celebrities stopped to take in its glow, and was moved to an area museum in 1977.

Between 1924 and the outbreak of the Second World War, the Phoebus cartel attempted to fix prices and sales quotas for bulb manufacturers outside North America. Early bulbs had lives up to 2500 hours, but the cartel agreed to limit life to 1000 hours. When exposed in 1953, General Electric and other American manufacturers were banned from limiting bulb life.

Image source: Phoebus cartel

By 1964, improvements in efficiency and production of incandescent lamps had reduced the cost of providing a given quantity of light by a factor of thirty compared with the cost at the introduction of Edison's lighting system.

The concept of high-efficiency incandescent lamps was pioneered by Duro-Test in 1980 with a commercial product that produced 29.8 lumens per watt, far above typical incandescent performance.

In 2007, General Electric announced a high efficiency incandescent (HEI) lamp project, claiming it would ultimately be as much as four times more efficient than current incandescents. The program was terminated in 2008 due to slow progress.

Image source: General Electric

A 2017 review in the World Journal of Biological Psychiatry reported that blue-rich white LED lighting can suppress melatonin and disrupt sleep and circadian rhythms, with potential implications for mental illness.

Image source: Light-emitting diode

In 1925, American chemist Marvin Pipkin patented a process for frosting the inside of lamp bulbs without weakening them, and in 1947 he patented a process for coating the inside of lamps with silica.

Image source: Marvin Pipkin

Corning installed the Ribbon Machine in 1926 at its Wellsboro, Pennsylvania factory. It surpassed previous automation attempts and produced incandescent bulbs into the 21st century; Gray's machine was producing 1,000 bulbs per minute by 1939. The 2016 closing of Osram-Sylvania's Wellsboro plant shut down one of the last ribbon machines in the US.

Image source: Corning Inc.