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Lighting Advancments Essay Research Paper Have you

Lighting Advancments Essay, Research Paper

Have you wondered why streetlights are yellow, or why the year 2000 cars have brighter headlights and they are a different color? Have you ever wondered how the indiglo light on your watch works, or why it glows green and not white? And did you know that same indiglo light can be used while frozen, dipped in water, bent in half, stepped on, or in hazardous environments. Lighting has changed over the last few years; there are advantages and disadvantages of different kinds of lighting.

Lighting has been around since time itself existed; the first kind of lighting was fire. Fire was used to warm the inhabitants, and to provide light; many primitive cultures would use burning torches to provide light for their excursions and pathways. Fire was the only true form of light they had other than the moon. Fire had many disadvantages, one was that fire depended on fuel and needed proper conditions to operate (no rain, minimal wind). Another disadvantage is that fire, if not handled properly, could result in a brush fire or even burn down their shelter. An advantage was it was efficient when conditions were correct. It provided an inexpensive form of lighting, and could be used for cooking and heating. Due to the persistent problem of limited fuel, inhabitants looked for a way to prolong the fuel. (Thwig 29-34)

The next step in lighting that followed was a candle. Candles offered one main advantage over the fire by itself, fuel. A candle was able to provide a long burning light and was relatively inexpensive to produce. Candles were originally made from whale fat. The flame would burn and would slowly use the wick as a fuel and would burn much slower because the wax slowed the burning down. (Thwig 35-49)

The next form of lighting that followed the candle was the oil lamp. The oil for the lamps was also made from whales. The oil was the primary fuel for the fire, it burned even longer than a candle, and was cleaner. The wick was submerged in oil with one side sticking out. The oil would travel up the wick to the exposed portion. When lit the wick would be saturated with oil and the fire would burn the oil on the wick. This form of lighting was a large improvement, many cites adapted to this technology. Cities would create streetlights from the lamps and they would be lit on a nightly bases. The light would illuminate the streets and provide for a safer community. The lamps were also used in homes and offices to provide light and allow for work at night. The candle and oil based lamps still had many downfalls. One problem was that the application still used fire as the source of light. The fire would omit carbon monoxide and always posed a threat if the fire was not watched closely. The oil-based lamps could fall over and would create a large fire by igniting all the oil at once, burning everything flammable around the lamp. (Hayward 23-25)

The next form of lighting was the incandescent lighting, more commonly known as a light bulb, which depended on electricity.

Thomas Alva Edison devoted all his adult life to science. Once Thomas Edison had enough money to be comfortable, he opened a laboratory in New Jersey. He then hired a team of scientists and gave them everything they needed to work; their job was to dream up new inventions . October 21, 1929 was the fiftieth anniversary of Edison s invention of the electric light. (Louis 46-48)

The electric light was a huge scientific discovery. The electric light offered a safer, non-fire based source of light. The lighting was dependent on no fuel (other then electricity) and was widely available for purchase or replacement. The light was also brighter and was more efficient than the previous forms of lighting. Currently, we still use incandescent lights, but our bulbs are far more advanced than its predecessors. (Louis 48-49)

Humans are now dependent on lighting and could not continue with out it in many cases. Light bulbs have become far more advanced in 1990, because of specialty bulbs, which are available to the general public. The bulbs come in a wide variety of colors and offer many unique options. Some of these options are, self-dimming lights, timed lights, even pure white lights. Pure white lights have a special coating, which offer a clean white light, instead of the standard yellowish light, which is most common. ( Ligthing F.A.Q. )

Another relatively new form of lighting is a halogen bulb. Halogen bulbs offer a brighter light than conventional lighting. These bulbs run much hotter than other kinds of lights.( Hubble Lighting )

Halogen bulbs can be used to light art work or special areas. The reason that these bulbs can be used for many different applications is because they can be aimed and the wattage varies from bulb to bulb depending on your application. (Neitzke)

Halogen bulbs are also used in the newer cars. New cars use halogen bulbs because they are twenty percent brighter. Another advantage of these lights is than are much easier to focus than an incandescent bulb because they have a very reflective backing and a lens is used to focus the light. Halogen bulbs produce whiter light than incandescent bulbs and use about the same amount of electricity. (Neitzke)

There are many kinds of lights that are used only in special situations; one of these kinds of lights is a street lamp. Originally, the streetlights used were mercury vapor bulbs (Neitzke). These lights produced a very brilliant white color and provided efficient lighting on the streets. The problem was that astronomers could not see the stars because of light pollution. Light pollution is when the lights illuminate the sky as well as the street. The astronomer s complaint was taken earnestly and the city changed all the streetlights to high/low pressure sodium lights (Neitzke). High-pressure sodium lights produce a brighter yellow glow than low sodium lights. These new lights provided a yellowish light and had minimal light pollution. (Neitzke)

Another form of lighting is security lighting. Security lighting has a special term to many people. People depend on these lights to be on for long periods of time and to provide a good deal of light. Previously many business and individuals used quartz lights. They provided a great deal of light but cost a great deal of money to run. For large areas, high-pressure sodium lights are now being used. These lights use one fifteenth of the power and provide the same amount of light. Homes can now replace incandescent security lighting with newer florescent lighting. Florescent bulbs will run longer and cost anywhere from half to a quarter of what an incandescent bulb would cost. Another advantage is that the florescent bulb life is near double that of standard incandescent bulb is. ( Lighting F.A.Q 2)

Another advancement in lighting that is now being used is motion lighting. This kind of lighting will turn the lights on when movement from a human or animal is detected. These lights have a main sensor which controls a switch, which triggered will turn on the lights for a set amount of time. These kinds of lights are used primarily for security reasons. They can be put on the dark side of a home and will turn on only when needed, also they save money. Another way these lights are being used is in the home. The light switch is placed where the switch will normally be located. The switch is just a semi-clear piece of plastic that detects movement and operates the same way as a security light. ( Hubble Lighting )

Decorative lighting has experienced another advancement. These kinds of lights have a special purpose; they illuminate an object. Decorative lighting is most commonly found in museums and art shows. But it is not uncommon to find it used in landscaping. The lamps are designed to output anything from a very brilliant focused beam of light to a large evenly distributed form of lighting; they are also available in many colors. In landscaping the lights are often used to outline pathways. The lights are also used to light up trees and other points of interest. ( Hubble Lighting )

A fairly new form of lighting is, fiber optics. Fiber optics is not used to illuminate large areas, but instead it is used to create unique displays of light. The displays have pinpoints of light, which are very brilliant. The display can change many colors from white to a brilliant purple to a dark blue all in the matter of seconds. The way this works is there is a powerful bulb in the base of the display. The bulb is positioned behind a rotating disc. The disc has numerous colors placed on it, the colors are the choice of the customer or producer and in many cases can be changed. The disc then rotates in a circle and the light shines on one side of the disc, creating numerous colors. The altered light is then shined directly on a glass fiber. Fiber optic cable is just crushed glass that has been reconstructed into a thin wire of all glass. The light travels through the glass. The glass acts like a tube, if focus s all the light to the very tip of the fiber optic strand. When it reaches the end of the strand it is visible to the human eye, and the light is still very brilliant. These forms of lighting can be found in many movie theaters now and are used to make novelty gifts. Also there is a new advancement in this area of lighting. They use this lighting to illuminate swimming pools; it works the same way just on a larger basis. The fiber optic cables are much thicker and cost significantly more. The pool then changes colors while you have the lights on; it creates a breath taking effect. (Neitzke)

Another form of lighting is emergency lighting. This is probably not the most interesting, but it is the most important. This kind of lighting can save our life by giving us the few precious minutes needed to get into a safer environment. Emergency lighting is required in new commercial complexes, as well as at school. When power is lost a small twelve-volt battery powers the lights. The battery is constantly charged while the power is on and normally offers four hours of emergency light. The form of emergency lighting used on planes is called electro-luminescent lighting. This kind of lighting uses very small electricity and offers a very clear and rugged form of lighting. ( Design Guide 1.0)

Electro-luminescent lighting is one of the largest advances in lighting. ELL is emergency exit lighting systems… its used by over 300 airlines and airline manufactures ( Design Guide 1.0).

The EL is constructed using a thin polymer substrate with a clear conductive coating. This is used as a base and the clear conductor allows the lights in the phosphor to be seen. This sheet is usually one hundred seventy-five thousandths of a millimeter thick. The whole lamp is therefore very thin and flexible. ( Why Electro-luminescent Lamps 1)

In simpler terms the lamps are very thin and are covered in a clear coat. Inside there is a phosphor layer that is outlined by two conductors on each side. The conductors are powered by one hundred ten volts and thus create the lighting effect. When power is applied the conductors alternate charge (AC CURRENT) when the charge is altered it excites the phosphor. The phosphor is a good insulator and uses very little current ( Why Electro-luminescent lamps 2). The phosphor has such a reaction it starts to produce a soft but brilliant glow evenly across the lamp. Your watch is a good example of an electro-luminescent lamp. Indiglo lighting is produced using electro-luminescent lamps and a transformer, which increases the voltage enabling the Indiglo to work. The most common applications that this form of lighting is used in is; backlighting, membrane switches, push boards, billboards, road signs, and safety lights ( Electro-luminescent 2). Also electro-luminescent lighting is very rugged, it is waterproof and is able to with stand freezing temperatures. Also it can handle shock and hazardous environments, something all the rest of the lights previously mentioned have trouble doing. ( Why Electro-Luminescent lamps )

Lighting has and will continue you changing throughout the rest of history. Humans depend on light, we revolve around power and as long as we depend on it, we will always want better products. Electro-luminescent is just one form of lighting that has been discovered but even it is not fully utilized yet. In the coming years we will see displays of light we cannot even imagine, displays we cant even think about in our wildest dreams. But one thing is for sure lighting has, and always will be a necessity of our culture.

Works Cited

The Design Guide. New Hampshire. Loctite Luminescent Systems Inc.1990, Revision 0490.

Edison, Thomas Alva. Frank & Wagnall s New Encyclopedia. 1989 ed.

Electro-Luminescents. Memtonik Innovations. Online. Pacific Bell, 7 January 2000. N. pag.

Hayward, Arthur H. Colonial and Early American Lighting. Canada; General Publishing Company, 1962.

Hubble Lighting Hubble. Online. Pacific Bell, 23 January 2000. N. pag. Available http://www.hubble-ltg.com.

Lighting F.A.Q. Rudd Lighting. Online. Pacific Bell, 22 January 2000. N. pag. Available http://www.ruddlighting.com/.

Neitzke, Ron. Personal Interview. 16 Feburary 2000.

Sabin, Louis. Thomas Alva Edison. New Jersey Troll Associates, 1983.

Thwig, Leroy. Flickering Flames. Tokyo; Charles E. Truffle Company, 1962.

Why Electro-luminescent lamps. Industrial Tehcnology. Online. Pacbell, 7 January 2000.




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