Tungsten Filament

Some articles on tungsten, filament, tungsten filament, filaments:

Luminous Efficacy - Lighting Efficiency - Examples
0.15–0.3% Incandescent 100–200 W tungsten incandescent (230 V) 13.8–15.2 2.0–2.2% 100–200–500 W tungsten glass halogen (230 V) 16.7–17.6–19.8 2.4–2.6–2.9% 5–40–100 W ... No substance is solid and usable as a light bulb filament at temperatures anywhere close to this ... The surface of the sun is not quite that hot.” At temperatures where the tungsten filament of an ordinary light bulb remains solid (below 3683 kelvins), most of its emission is in the infrared ...
Incandescent Light Bulb - Filament
... The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo) ... Early carbon filaments had a negative temperature coefficient of resistance — as they got hotter, their electrical resistance decreased ... in the power supply, since a small increase of voltage would cause the filament to heat up, reducing its resistance and causing it to draw even more power and heat even further ...
Mazda (light Bulb)
... In 1909 the Mazda name was created for the tungsten filament light bulb ... General Electric promoted the mark as identifying tungsten filament bulbs with predictable performance and life expectancy ... General Electric also licensed the Mazda name, socket sizes, and tungsten filament technology to other manufacturers to establish a standard for lighting ...