In modern culture, the lightbulb is the symbol we often use to denote a sudden flash of inspiration. It is ironic, then, that the lightbulb itself is not the result of just one exceptional idea, but followed the contributions of many men over several decades. Thomas Edison is often credited with the design for the first practical lightbulb, but he was not responsible for the early developments. Without the input of American chemist Irving Langmuir (1881-1957), the lightbulb as we know it today might not have existed.
In the late nineteenth century, Edison filed numerous patents for improvements to electric lighting. His 1880 patent application for an electric lamp certainly depicts what we would immediately recognize as a lightbulb. But it was Langmuir's improvements to the filament at its core that gave us the lightbulb's modern design.
Langmuir was a researcher at Edison's General Electric Company, where he was studying the chemical reactions of tungsten inside lightbulbs. The company had replaced its old carbon filaments with tungsten, which lasted longer but was prone to vaporize very quickly, causing the bulbs to become black and dim. Langmuir slowed down this evaporation process by coiling the filament and adding nitrogen, a fairly unreactive gas, to the bulb.
The improved filament and lightbulb design was patented on April 18, 1916. It is essentially the design that is still used, although argon is now the unreactive gas most commonly used in lightbulbs.
Langmuir went on to win a Nobel prize in 1932 for his contributions to surface chemistry.