Man’s main and natural source of light is the sun; the gigantic burning mass which produces illumination to the solar system, the earth inclusive; along with heat and radiation. Our awareness is in no doubt that the sun is central and stationary in the system. Also, the rotations on their own axes and revolutions about the same sun, of the Earth and other planets, would intuitively fluctuate the availability of illumination. Consequently, day and night emerged.
IN THE BEGINNING THERE WAS LIGHT
Thousands of years before science became organized, fire was discovered. It did presented “smaller suns” because of the heat and light produced. Fire, however, extinguishes if it means of sustenance drops or exhausts. Without doubt, a big problem with “artificial light” is its sustenance. Starting with many crude and localized materials, man began to find solutions to this problem; “artificial light” should last longer. There will no discussion on fuels here, mind you.
WHO DID WHAT?
Thomas Edison is often honored for his work on incandescent light. However, books of history have it that he did not actually invent the light bulb, but created the first commercially practical incandescent light. Many great scientists and inventors had worked on incandescent light before him. Edison’s interesting 1000-times trials makes his side of the history of “artificial light” more interesting than others. It was, and still, very motivational.
Sir Humphry Davy invented the “The Electric Arc Lamp”, using a glowing carbon; the light was weak and did not last long enough. That was the first “electric light” to be invented in 1802 with carbon as the filament. In 1840, platinum was used as the filament Warren de la Rue. It worked efficiently. In fact, longevity was improved, because platinum could be operated at high temperatures. But there was a major problem; commercial production was not feasible, because of the high cost of platinum.
THE PROBLEM IS THE FILAMENT
There is no argument in this, as getting the right filament was the real problem. The filament is the part of the devices that produces the light. When electric current goes through the filament; it glows. This glow is caused by the heat generated through the filament’s high resistance to the flow of the electric current.
There had to be an element that would fit in nicely by combining both the technical and commercial conditions. Carbon filament could irritatingly blacken tubes and did not last long. Platinum is not economical because of its high cost. Although, it could endure heat, a quality necessary for the production of light, the market price would never be friendly.
Edison and his team even improvised with carbonized bamboo filament that could last over 1200 hours. It was the beginning of commercially manufactured light bulbs and the formation of Thomas Edison’s company; Edison Electric Light Company, in 1880. The company marketed the new product. That was never the end of the story.
TUNSGTEN DID THE MAGIC
This is awkwardly interesting! Edison, himself, knew that tungsten would be good as a filament for incandescent light, but, he had no means of refining the element. Anyway, tungsten did the magic! Another company, General Electric, had one of their scientists, William David Coolidge, worked on tungsten and made it the best filament for incandescent light.
Why tungsten? Tungsten has a very higher melting point of about 3422 degree-Celsius. For a typical incandescent light bulb, the Tungsten filament operates at approximately 2500 degree-Celsius. Its boiling point is around 5555 degree-Celsius. Its density is 19.25 g/cubic-cm. In addition, it does not cost as high as platinum, which makes it commercially relevant.
Although, “artificial light” has moved on from that stage, nonetheless, the element-tungsten did the magic. It solved the problem of light bulb filament!