Who Invented the Light Bulb

Who invented the lightbulb? You might be surprised by the answer. The lightbulb is a popular invention, and most people have a ready answer for this question, but there's more to the lightbulb than meets the eye.

Was the Lightbulb Invented in 1806?
Humphrey Davey, from England, deserves credit for his important role in the invention of the lightbulb. In 1806, Mr. Davey met with the Royal Society to demonstrate his electric lamp. The lamp worked by using two charcoal roads parallel to one another to create a powerful electric spark. This effect was similar to the Jacob's Ladder high-voltage effects you see in electronics labs and in mad scientist movies from the '50s and '60s.

Unfortunately for Davey, this electric lamp was impractical for residential or even commercial lighting. The light was just too harsh and bright to be utilized in either of these settings, so Davey's electric lamp didn't find a commercial audience at that time.

However, as technology improved and power sources evolved that could feed the arc lamp for sustained periods of time, it found a home in applications that called for extremely bright light sources. These applications included lighthouses, searchlights and lighting public areas. Descendents of these arc lights are still in use in some searchlight applications today.

Incandescent Bulbs
Incandescent lighting seemed the most practical electric light source, but incandescent materials would melt or burn in most applications. To counter the flammability, several inventors enclosed incandescent materials in glass bulbs and pumped out the oxygen, making it impossible for the materials to ignite. The vacuum inside these glass bulbs was an integral part of the invention of the lightbulb, but none of the bulbs contained a source that would last long enough to be practical for everyday use.

Enter Thomas Edison
When he began working on the problem of the light bulb, Thomas Edison had already successfully developed and commercialized several other products. His specialty was in examining existing technology and adapting it to be more commercially successful. 

Edison's first attempts at a lightbulb produced an electric bulb with a temperature-sensitive switch that shut off the current when the bulb got too hot. This was supposed to prevent the incandescent material from burning out. However, the bulbs flickered too much to be useful, so Edison needed another approach.

He hired a physicist, Francis Upton, and put together a team with the intention of developing a lightbulb. The team researched existing patents to eliminate avenues that had already been explored. Upton began looking at the properties of the incandescent material itself. By the end of 1880, Edison's team had developed a carbonized bamboo burner that provided almost 600 hours of light before burning out.

Edison went on to methodically test more than 6,000 different materials for use as light bulb filaments, carbonizing them to help them last. Over the next several years, several new lightbulbs were invented and patented, all with improved filaments, creating practical, replacable lightbulbs with longer lifespans. While Edison didn't invent the concept of the light bulb, he did develop the basic shape, design and filament concepts that are still in use today.