How an Incandescent Light Bulb Works

If you ask someone to draw a light bulb, you are most likely to see him draw an incandescent bulb. This is one of the reasons why I am quite positive that a lot of people will agree that this light bulb can easily be proclaimed as the most popular light bulb in history. This is also no surprise given the fact that this light bulb has served us for over a millennium since Thomas Edison invented it in the late 1800s and is still being used today.

But how does this popular light bulb work? Just basing on the bulb’s name, I would say it works through the use of incandescence. Incandescence is simply the emission of light by an object as the effect of its temperature or state of being hot and known to be a special case of thermal radiation.

This idea is encased within our incandescent bulbs but with just some twists to make it safer and more economical for our home use. It produces light by the use of a filament wire that is heated to a very high temperature with the use of electricity in order to produce light.

Electricity goes into your incandescent bulb through the hot wire that is connected to the tab found on its base. Then the electricity travels into the bulb through a thin wire that goes to a piece of metal coil. Tungsten is the primary metal used in this type of bulb because it has a very high melting point which makes it ideal to be heated at high temperature.

You will find the tungsten coiled within the bulb to its maximum resistance. Once electricity comes in contact with the resistance, it heats up the resistor. Then the tungsten coil is heated up to 2482 degrees Celsius or 4500° Fahrenheit. This extreme temperature makes the metal white hot thus producing the glow we see as light.

You may notice the tungsten coil and the other components attached to it are encased in a glass bulb. This is to keep oxygen away from the tungsten which can make it burn up immediately and to also encase an inert gas within it, usually argon, which improves luminous efficacy and reduce the bulb’s blackening. Also, the bulb encasement helps protect the users from being electrocuted from the wires and burnt from the tungsten filament.

The electricity completes its journey from the wire to the tungsten back down another wire to go out of the bulb through the metal portion found on the side of the socket. This then goes to the light fixture then out the white wire.

This is simply how the incandescent light bulb made use of incandescence combined with practical improvements to make it the longest used electric artificial lighting source in history.

This light bulb however is now deemed to be energy inefficient given the fact that most of the energy it consumes (around 80%) is converted to heat energy rather than light.