How Light Bulbs Work and Were Invented

We all know how light bulbs work. When referring to the simple lightbulb found in most homes: these work by screwing the lightbulb into a socket and then moving a switch up or down depending on if you want the light bulb on or off. Of course this is a simplified explanation and answers a question more of how to use a lightbulb than actually how light bulbs work. For those interested in the latter, we’ll give a more detailed explanation below.

A standard incandescent light bulb has two metal pieces at its base. In order for the light bulb to work, these metal connectors need to touch a power source, usually from an electrical outlet or a number of batteries. The electrical charge then travels in a loop from one connector to another, delivering power to the bulb’s filament.

A filament is the wire you’ll find in the center of a bulb’s glass enclosure. This is no ordinary wire as it is one that needs to support 2500 degrees centigrade for most bulbs, and therefore is made from a metal with a very high melting point. That metal is tungsten.

The actual light is produced when electrons from the power supply make rapid contact with the filament’s atoms. This contact produces vibration creating friction that produces heat, otherwise known as thermal energy. The end result is heat/thermal energy being captured and released by the electrons in the form of photons (light).

Quality and types of light bulbs vary greatly, and as you navigate other pages of our site, you’ll find some additional information specific to how light bulbs work for each grade, scale and type.

To understand a little more how lightbulbs work, let’s look at the history of light bulbs relating to their invention.

History and Invention of the Lightbulb

As simple as a lightbulb seems, it was not an easy invention. There is a term, don’t try to reinvent the wheel, and, of course, the saying makes a lot of sense, but the task would be incredibly easier than to try to reinvent the lightbulb. In fact, it is still to this day being done, but with records of the failures in its history. The main reason for the experimentation involved is to provide greater efficiency, as the modern incandescent lightbulb provides only about 5% light and the rest of the power is wasted as heat.

The story goes all the way back to 1802, when Humphrey David created the first incandescent light by passing an electric current through a thin strip of platinum. It worked, but it was neither bright enough nor did it last long enough to be of practical use. The story continues with others forming their ideas into workable creations, and in 1841, Frederick de Moleyns of England was granted the first patent for an incandescent lamp which contained platinum wires within a vacuum tube. But another British scientist, Warren de la Rue, had already done that the previous year and found that the high cost of platinum made it impractical.

Other inventions followed, some using carbon or other materials, and patents were granted. Still, it was the element within that stopped the lightbulb from being practical for commercial use. The first major success came in 1880, when Joseph Wilson Swan, a British physicist and chemist, developed a better carbon filament which also used treated cotton fibers. After receiving a British patent, he went on to power his house, the world’s first house to be illuminated with an electric lightbulb, which was powered by Hydro Electric Power, his own company.

Thomas Edison, who had continued his work on the lightbulb before and during this time, applied for and received a patent in January of 1880, in which he described various ways of producing the carbon filament. Then many months later, he developed a filament of carbonized bamboo which lasted over 1200 hours.

There were others around this same time who were diligently working on the lightbulb. There was a lightbulb company started by Hiram S. Maxim, the United States Electric Lighting Company, the second after Edison’s Company, to sell practical incandescent bulbs. There were lawsuits, and major among these was the one filed against Edison by Swan who sued Edison and won. The two inventors joined in Britain to form the Edison and Swan United Electric Company. Edison, in the end, acquired Swan’s interests in the company. After many more years of litigation, a judge ruled in 1889 that Edison’s claim of a “filament of carbon of high resistance” was valid.

The history of the “simple” lightbulb went on, and there were other inventions which were improvements to the element; some had the addition of various gases, some treated the glass of the bulb. All of this history became important to developments of various types of lightbulbs, including the gas xenon, which is used today. The major efforts have been for the cause of efficiency, as the incandescent lightbulb, although inexpensive itself, is highly inefficient.