Primelite continues our look at the different types of light bulbs. From Incandescent to LED, lighting has changed immensely over the past 200+ years. In the past weeks we’ve taken a look at Incandescent Bulbs and Reflector Lamps (Incandescent). This week we’ll explore Tungsten-Halogen Lamps.
What is a Tungsten-Halogen Lamps.
The Tungsten-Halogen lamp, also know as Quartz-Halogen, Quartz Iodine or Halogen lamp, is an incandescent light that includes a halogen gas (iodine, bromine). As in regular incandescent bulbs, the halogen bulb contains a tungsten filament. This combination of halogen gas and tungsten filament produces a light of higher illumination and color temperature in a smaller sized bulb.
One drawback of the tungsten-halogen lamp is the extreme heat output. Because of the heat, tungsten-halogen lamps are constructed of a much thicker glass typically made of fused quartz, high-silica glass or aluminosilicate. The bulb also produces a “bluer” white light, closer to sunlight, when compared to the “warmer” white produced by ordinary incandescent bulbs. The lamps also offer “full on brightness” and are dimmable.
The small size of the tungsten-halogen bulbs make them perfect for use in residential and commercial track lighting, recessed lights (cans), in retail environments and for product display lighting. The television and film industries have long embraced the tungsten-halogen lamp due to their lumen output and size.
Tungsten-Halogen lamps come in numerous sizes and configurations, the most common being single or double ended (single containing one bulb, double two). The double ended lamps are generally used for work lights and film production lamps. The most common single bulb tungsten-halogen lamp is the MR-16.
MR-16 bulbs are the workhorse of the tungsten-halogen family. These “multifaceted reflector” (MR ) lamps consist of a halogen bulb integrated with a glass reflector. The reflector can be faceted or smooth resulting in different beams, from narrow spot lights to wide flood lights. MR-16 bulbs are very useful for directional lighting and are used in track lighting, recessed cans, pendent fixtures, desk lamps, landscape and retail lighting.
While there are many advantages to the tungsten-halogen lamp, there are a few disadvantages. As previously mentioned the bulbs do get extremely hot, which can lead to an explosion, resulting in the need of a protective glass over the bulb. The bulbs themselves must not be touched by human fingers because the skin oils left behind can lead to bulb failure. Even with these problems the tungsten-halogen lamp has proved to be very important to the lighting field.
As with all incandescent bulbs, the tungsten-halogen lamps are being phased out and replaced with LED versions which are more efferent, do not have temperature issues and are cheaper to light.
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