electric-filament lamp

lighting

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June 26, 2026

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An electric-filament lamp, also known as a lightbulb, is a type of incandescent lamp. It produces light by heating a fine electrical conductor, called a filament, to a high temperature using an electric current. This filament is enclosed within a glass shell, often filled with an inert gas like nitrogen to prevent the filament from burning out. Early versions used carbon filaments, but more efficient tungsten filaments were later developed. While initially a significant advancement over gas lighting, incandescent lamps have largely been replaced by more energy-efficient technologies like fluorescent and LED lamps due to concerns about energy consumption and global warming.12

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Electric lamps
The electric filament lamp, which came into general use in the 1920s, became the standard illuminant. Power output ranged from about 1,500 watts for the largest structures down to about 5 watts for buoys and minor beacons. Most lamps were of the tungsten-halogen type for better…
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The electric filament lamp, which came into general use in the 1920s, became the standard illuminant. Power output ranged from about 1,500 watts for the largest structures down to about 5 watts for buoys and minor beacons. Most lamps were of the tungsten-halogen type for better…
Read More