Lighting

BRINGING LIGHT INTO HOME

For the ancestors of humankind that lived thousands of years ago, darkening sky meant that it was time to stop every activities and hide in a safe place till the sunrise. Nocturnal preys had senses that were better adapted to darkness than ancestors of humans (who had eyesight that was not very different from ours), and the only way to prevent their attack was to find a safest place to sleep and hope the sunlight to come out.
About 790,000 years ago, human ancestors discovered that fire could bring back light during nights, and could scare animals away. First time they obtained from natural forest fires, but later they figured out a way to use flint, dried moss and bark to light fire. That was when human beings could control light and darkness during night times; now it was possible to do continue their activities even at night, even in the deepest cave. Not all pebbles were suitable for flints and it was extremely valuable; many tribes fought and killed other tribes in order to obtain/defend flints from others.

790000 BC ~ 700 BC

Ancient Candles


Ancient civilization used natural fuels and flint to light up their dark cave and homes. They would soak dried moss with animal fat and burn it in a hollow stone or shell, or in some places burn a dried candlefish (a.k.a. Eulachon, or oilfish; kind of fish that preserves lots of fat in its body). As humans began to produce pottery, the shape of lamps began to vary in different places. Wicks were later invented to control the rate of burning, which usually was made from dried plants or fiber. Around 7th century BC, the Greeks made terra cotta lamps to replace the simple handheld torches (the word lamp is derived from the Greek word lampas, meaning torch). Early lighting fuel consisted of olive oil, beeswax, fish oil, whale oil, sesame oil, nut oil and etc, contained in pots.



~ 1800 AD

Oil Lamp


Although an oil lamp was used ever since fire was discovered in ancient times, a major improvement was made in lamp design as the central burner was invented. Now the fuel was enclosed in metal vessel and you could control the intensity of the fuel burning and intensity of light by the adjustable metal tube. A while later small glass chimneys were added to the design to protect the flame (and the environment, since lamps were usually used indoors) and to control the flow of air to the flame. A Swiss chemist, Ami Argand, was credited with first developing the principal of using an oil lamp with hollow circular wick and the glass chimney in 1783. In 1859, drilling for petroleum oil began and kerosene (petroleum derivative) lamp grew popular.



1800 AD

Gas Light


William Murdock, a Scotsman is generally regarded as the father of gas lighting. In 1792 he heated coal to produce natural gas and used it to light his home and office in Cornwall, England. German entrepreneur Frederick Winsor was the first person to patent coal gas lighting in 1804 and a "thermolampe" using gas distilled from wood was patented in 1799. His main interest in gas was for street lighting. In 1809, Windsor established the first public gas company, The Gas Light and Coke Company, which remained in existence until the company was nationalized in 1948. Early in the 19th century, most cities in the United States and Europe had streetlights that used gas fuel; gas lights on streets were very popular because gas lights could light themselves, without help of a person.



1870 AD

Incandescent light bulb


Incandescent lamp is the most common method of lighting used in current era. Sir Joseph Swann of England and Thomas Edison both invented the first electric incandescent lamps during the 1870s, but Thomas A. Edison's lamp became the first commercially successful incandescent lamp Edison received U.S. Patent for his incandescent lamp in 1880. Contrary to popular belief, Thomas Alva Edison did not "invent" the first light bulb, but rather he improved upon a 50-year-old idea. The two inventors that patented an incandescent light bulb before Thomas Edison could not raise the financing to commercialize their invention. However Thomas Edison, who had been working on the same idea, bought the rights to their patent with his syndicate of industrial interests with $50,000 to invest - a sizable sum at the time. Incandescent lamps require a low manufacturing cost, and work well on either alternating current or direct current. As a result the incandescent lamp is widely used in household and commercial lighting.




1962 AD

Light-Emitting Diodes (LED)


The light emitting diode (LED) is p-n junction semiconductor lamp which emits radiation then biased in a forward direction. The emitted radiation may be either invisible (infrared) or in the visible spectrum. LED's are commonly used in indicator lighting applications. Due to their very long life and low operating current, they are ideal replacements for incandescent lights. Early LED's came in red only. These red LEDs were bright enough only for use as indicators, as the light output was not enough to illuminate an area. Next green and amber were introduced. By the mid 1990's blue and white LED's had been developed. As the LED materials technology became more advanced, the light output was increased, while maintaining the efficiency and the reliability to an acceptable level, causing LEDs to become bright enough to be used for illumination, in various applications such as lamps and other lighting fixtures.

Many experts agree that if developed further, LED could replace incandescent light bulbs and fluorescent lamps in near future; especially because the fact that the earth is running out of fossil fuels is a major concern in every countries all over the planet, and many researches have been made to figure out a way to use less fuel and energy to replace current lighting system.