Search results
Results from the WOW.Com Content Network
The temperature of the ideal emitter that matches the color most closely is defined as the color temperature of the original visible light source. The color temperature scale describes only the color of light emitted by a light source, which may actually be at a different (and often much lower) temperature. [1] [2]
Most of the bulbs in circulation are reproductions of the wound filament bulbs made popular by Edison Electric Light Company at the turn of the 20th century. They are easily identified by the long and complicated windings of their internal filaments, and by the very warm-yellow glow of the light they produce (many of the bulbs emit light at a ...
Like all incandescent light bulbs, a halogen lamp produces a continuous spectrum of light, from near ultraviolet to deep into the infrared. [23] Since the lamp filament can operate at a higher temperature than a non-halogen lamp, the spectrum is shifted toward blue, producing light with a higher effective color temperature and higher power ...
The filament in a tungsten light bulb is not easy to break when the bulb is cold, but filaments are more vulnerable when they are hot because the incandescent metal is less rigid. An impact on the outside of the bulb may cause the filament to break or experience a surge in electric current that causes part of it to melt or vaporize.
In 1905, Just and Hanaman patented a process for producing tungsten filaments by plating carbon filaments with tungsten, then removing the carbon by heating. [4] These early tungsten lamps were more efficient than a carbon filament lamp, because they could operate at a high temperature, due to the high melting point of tungsten.
In photography, mireds are used to indicate the color temperature shift provided by a filter or gel for a given film and light source. For instance, to use daylight film (5700 K) to take a photograph under a tungsten light source (3200 K) without introducing a color cast , one would need a corrective filter or gel providing a mired shift
With HMI bulbs, color temperature varies significantly with lamp age. A new bulb generally will output at a color temperature close to 15,000 K during its first few hours. As the bulb ages, the color temperature reaches its nominal value of around 5600 K or 6000 K. With age, the arc length becomes larger as more of the electrodes burn away.
The name "Tungsram" is a portmanteau of tungsten (/ ˈ t ʌ ŋ s t ən / TUNG-stən) and wolfram (/ ˈ w ʊ l f r əm / WUUL-frəm), the two common names of the metal used for making light bulb filaments. Before becoming nationalized by the Communist government in 1945, the company was the world's third largest manufacturer of light bulbs and ...