|
There are two common sources of artificial light - the incandescent bulb and the fluorescent tube. Light bulbs and tubes can be grouped in general categories according to the way they produce light. They are installed in ceiling fixtures, floor and table lamps, and structural light designs that direct the light to where it is to be used.
Incandescent light source
The incandescent light is the kind used most frequently in our homes. The light here is produced by a tungsten thread that bums slowly inside a glass bulb. Fluorescent Tubes
Fluorescent light is produced when electrical energy and mercury vapour creates an arc that stimulates the phosphorous coating on the inside of the tube, and the light spreads evenly from the entire surface of the tube, it spreads in all directions, creating a steady, shadowless light. Tubes require a ballast to ignite and maintain the electrical flow called a choke.
Fluorescent tubes last for longer period than incandescent bulbs. Unique advantage of fluorescent sources is their linear quality, which is handy in lighting some architectural elements such as valances, coves, cornices and brackets and for installations along the length of a surface such as study table, kitchen cabinets and shelves.
The fluorescent tube installation is complicated and the fixtures are also costly. However, the tubes last longer, keeps the environment cooler, require fewer fixtures, produce less glare and use from one-third to one fifth less electricity than' incandescent light bulbs, which makes up for the initial installation costs.
Other sources of artificial light are the Quartz halogen bulbs, High intensity discharges and Neon bulbs which are used for specific purposes like the commercial display, whenever very bright light is needed or for specific art display
|
Participants