Lightbulb

By 22princess

  • 1802

    The first electrical light was invented by Sir Humphry Davy. He managed to pass a current through a platinum strip. This made the platinum strip glow.

  • 1809

    Sir Humphry Davy made the first carbon arc lamp by connecting 2 wires to a battery and placing a charcoal strip between the wires. The charcoal strip glowed but it used too much of the battery’s power too quickly.

  • 1840

    Warren de la Rue made a lightbulb that was able to operate at high temperatures. He placed a platinum filament in a tube and passed an electrical current through it. It glowed but the cost of platinum made it an impractical design.

  • 1841

    Frederick de Moleyns received the first patent for an incandescent lightbulb. An incandescent lightbulb is one that heats a metal filament and when it is hot enough it emits light.
  • Period: to

    1850-1870

    Joseph Wilson Swan replaced the platinum strips with carbonised paper filaments and enclosed it in a glass bulb. The lightbulb didn’t last long though due to the lack of an adequate supply of electricity. Then, by 1870, he managed to create a longer lasting lightbulb by using a treated Cotten thread that also stopped the bulb from blackening.

  • 1874

    Henry Woodward and Metthew Evans made more lamps using carbon rods held between electrodes in a glass bulb filled with nitrogen. They then patented their design.

  • 1878

    Thomas Edison bought Henry Woodward and Metthew Evans‘s patent and tested which metal filament worked best in the lightbulb. He ended up finding that the carbon filament worked the best. He then filed another patent for his lightbulb design.

  • 1878

    Joseph Swan filed a patent for his lightbulb.

  • 1879

    Thomas Edison found out that carbonised bamboo filaments could last 1200 hours.

  • 1880

    Thomas Edison started selling his new lightbulb.

  • 1882

    Thomas Edison took Joseph Swan to court because they were both making lightbulbs and they both had patents. Thomas Edison lost the case but he ended up joining his business with Joseph Swan.

  • 1903

    Willis Whitnew covered the carbon filament in the lightbulb with metal. This stopped the bulb from blackening.

  • 1906

    The General Electric Company (G.E.C) discovered that using a tungsten filament improved the lightbulb. They patented their design.

  • 1910

    William Coolidge, part of the G.E.C, improved the manufacturing of the tungsten filament. This made the cost more practical and the design took off. Tungsten filaments are still used in incandescent lightbulbs today.

  • 1913

    Irving Langmuir found that filling the lightbulb with an inert gas like nitrogen and twisting the tungsent filament made it last longer.

  • 1925

    Marvin Pipkin developed the first frosted incandescent lightbulb.

  • 1930

    Fliresent lights started to become popular.

  • 1956

    The halogen lightbulb was created. It consumed less energy and lasted longer.
  • Period: to

    1961-1972

    Colourful light emitting diodes were invented.

  • 1976

    The first compact fluorescent light (CFL) was created but not manufactured and sold.

  • 1985

    The CFL hit the market.

  • 1993

    Shuji Nakamura developed the first bright blue light emitting diode. After this development scientists started experimenting with colourful light emitting diodes and covering them with phosphors to make them appear white. Soon enough the first white LED light had been invented.

  • 2000

    LED lights hit the market.
  • Period: to

    2008-2018

    LED lights have improved and are continuously being improved and now last longer and are more efficient. The price of LED lights has also significantly dropped.