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This is the Working Principle Behind the Halogen Bulbs

The halogen bulbs of today are great. The halogen bulbs are the bulbs in which the halogen gas is for the filler gas. The most common use of the halogen is in the filament bulbs. In addition to this, also the lights with LED also are available with the halogens in them. The use of halogens increases the use of the lights.

Construction

In an incandescent halogen bulb, the tungsten filament has a covering of quartz. However, his is very small. It is very close to the filament and therefore it is to be made of quartz instead of glass.

Then the cavity of the bulb has the halogen gas.

Working of the halogen bulbs with the tungsten filaments

In the normal tungsten filament bulbs when we pass electricity the tungsten filament shows resistance. Due this, it opposes the passage of the electricity and therefore in this process it gets heated. The heat that this produces is very high. It vaporizes the atoms from the filament and therefore they go leave the filament. Because of this, the filament gets thinner and thinner. Moreover, because of this finally it becomes so thin that it eventually breaks up. Moreover, the atoms that evaporates because of the heating deposit on the walls of the bulb. Therefore, they block the light.

However if we fill the cavity of the bulb with the halogens the atoms of the filament which turn into vapor state and condense on the walls of the bulb, combine with the halogen atoms. Because of this, the gas removes the deposit from the walls and this makes the walls more transmitting for the light. Moreover, when they combine with the halogen atoms the combined atoms again go to the filament. There because of the heat the tungsten atoms from them again deposit on the filament as soon as they touch it. This maintains the thickness of the filament. Thus, it will improve the life of the filament. The halogen atoms again go into the vapor state and hence they can again combine with the atoms of the tungsten that may deposit on the walls of the bulb.

Thus, due to both of these factors the life of the bulb increases. The average increase of the life of the bulbs is around 10 to 20 percent. Not only this, the halogen also increases the efficiency of the bulbs in terms of the output at the similar wattage voltage and life expectancy. Due to process of recycling of the tungsten that is, constantly going on you it is possible to run these bulbs at higher temperatures. This gives better intensity of light than the normal light bulbs.

Sometimes these bulbs may last up to two to three times more than the ordinary bulbs. As there are different halogens like the neon xenon or krypton, argon etc, the efficiency of these bulbs also depends on these gases. If the bulb has the premium quality, krypton in most of the cases or, xenon or, argon then, the bulbs show good efficiency.

About the Author

Muna wa Wanjiru Has Been Researching and Reporting on Light Bulbs for Years. For More Information on Halogen Bulbs, Visit His Site at HALOGEN BULBS

How do you determine the wattage of a light bulb?

The temperature at which pure tungsten melts is about 3400 K. Assuming the filament of an incandescent light bulb has an operating temperature safely below this value, say 2900 K, at what wavelength does its spectrum peak? The filament has a diameter of 0.3 mm and a length of 10 cm. What is the wattage of the light bulb?

Tungsten melts at 3422 Celsius (3695 K)

At 2900 K the peak wavelength is 1 micron.

Tungsten has a resistivity of 90.4 microohm.cm at 3000K
and a resistivity of 87.3 microohm.cm extrapolated at 2900K.

the filament area is
pi * r^2 = 3.14 * (0.3*10^-3/2)^2 = 7.068E-8 m^2

the filament resistance is
87.3E-8 ohm.m * 0.1m/7.0689E-8m^2 =1.235 ohm

The power is P = V^2/R = (120V)^2/1.235ohm = 12 kW

This must be a very powerful spotlight.

House votes to defy feds on light bulbs
So, how many lawmakers does it take to invite a lawsuit by the federal government over what kind of light bulbs are legal?

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