What Is a Carbon Filament Light Bulb?

Written by melinda adams
  • Share
  • Tweet
  • Share
  • Pin
  • Email
What Is a Carbon Filament Light Bulb?
Carbon filament was replaced with tungsten at the turn of the century. (light bulb image by Photosani from Fotolia.com)

The earliest form of light bulbs contained carbon filaments. These were in use until the turn of the century, when the tungsten filament was invented. Incandescent bulbs today still use tungsten filaments.


Contrary to popular belief, the electric light was invented in 1809 by a chemist named Humphry Davy. He was able to create an arc of light by connecting a carbon strip to the ends of two wires which were connected to a battery. The main drawback was that the carbon filament did not burn very long. Electric light sources used variations of this method until 1876, when Thomas Edison created a carbon filament that would burn for 40 hours.

Edison's Role

Thomas Edison did two things to bring the light bulb into popular use: Not only did he invent a filament that would burn for 40 hours, he also placed the wires inside a vacuum bulb. This idea was based on a patent issued to Henry Woodward and Matthew Evans in 1875. Edison bought the patent from them in 1879.

The Move to Tungsten

In 1906, General Electric was issued a patent for a method to make tungsten filament light bulbs, though they were very expensive to produce. In 1910, William David Coolidge created a way to bring down the cost of the new lights, and they quickly replaced the old-style carbon filament bulbs.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the eHow.co.uk site, you consent to the use of cookies. For more information, please see our Cookie policy.