Glühlampe

A glühlampe, commonly known in English as an incandescent light bulb, is a type of electric light that produces light by means of a filament that is heated until it glows. The filament is typically made of tungsten and is enclosed in a glass bulb that is filled with an inert gas or a vacuum.

The principle behind the glühlampe is the incandescence of a solid material when it is heated to a high temperature. When electric current passes through the filament, its electrical resistance causes it to heat up significantly. As the filament reaches a high temperature, it begins to emit visible light. The color of the light produced depends on the temperature of the filament; higher temperatures result in a whiter light.

The invention of the practical incandescent light bulb is most often attributed to Thomas Edison, although several inventors contributed to its development. Edison's key innovations included a durable filament and a high-vacuum bulb, which significantly extended the bulb's lifespan. Early glühlampen had very short lifespans, often lasting only a few hours.

While once ubiquitous, glühlampen have largely been phased out in many parts of the world due to their inefficiency. They convert only a small percentage of the electrical energy they consume into visible light, with the majority being lost as heat. This low energy efficiency has led to the widespread adoption of more efficient lighting technologies such as fluorescent lamps and LED (light-emitting diode) bulbs. However, the simplicity of their design and their warm, familiar light quality means they can still be found in some specific applications.