The electric light bulb has been known as the most important invention since man-made fire. The light bulb helped to establish social life after sunset, extended the workday well into the night, and allowed us to navigate and travel safely in the dark. Without the light bulb, there would be no nightlife.

The electric light, one of the everyday conveniences that most affects our lives, was not “invented” in the traditional sense in 1879 by Thomas Alva Edison, although he have created the first commercially practical incandescent light. He was neither the first nor the only person trying to invent an incandescent light bulb. However, Edison is often credited with the invention because his version was able to outstrip the earlier versions because of a combination of three factors: an effective incandescent material, a higher vacuum than others were able to achieve and a high resistance that made power distribution from a centralized source economically.

EARLY LIGHT BULBS AND HISTORY:

In 1802, Humphry Davy invented the first electric light. He experimented with electricity and invented an electric battery. When he connected wires to his battery and a piece of carbon, the carbon glowed, producing light. His invention was known as the Electric Arc lamp. And while it produced light, it didn’t produce it for long and was much too bright for practical use.

Over the next seven decades, other inventors also created “light bulbs” but no designs emerged for commerical application. In 1840, British scientist Warren de la Rue enclosed a coiled platinum filament in a vacuum tube and passed an electric current through it. The design was based on the concept that the high melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain fewer gas molecules to react with the platinum, improving its longevity. Although an efficient design, the cost of the platinum made it impractical for commercial production.

In 1850 an English physicist named Joseph Wilson Swan created a “light bulb” by enclosing carbonized paper filaments in an evacuated glass bulb. And by 1860 he had a working prototype, but the lack of a good vacuum and an adequate supply of electricity resulted in a bulb whose lifetime was much too short to be considered an effective producer of light. However, in the 1870’s better vacuum pumps became available and Swan continued experiments on light bulbs. In 1878, Swan developed a longer lasting light bulb using a treated cotton thread that also removed the problem of early bulb blackening.

THOMAS ALVA EDISON AND HIS FIRST ‘LIGHT BULB’ :

Thomas Alva Edison was born on February 11, 1847, in Milan. He was the seventh and last child born to Samuel Edison Jr. and Nancy Elliott Edison, and would be one of four to survive to adulthood. Thomas Edison received little formal education, and left school in 1859 to being working on the railroad .

In 1878, Thomas Edison began serious research into developing a practical incandescent lamp and on October 14, 1878, Edison filed his first patent application for “Improvement In Electric Lights”. However, he continued to test several types of material for metal filaments to improve upon his original design and by Nov 4, 1879, he filed another U.S. patent for an electric lamp using “a carbon filament or strip coiled and connected to platina contact wires.”

Edison focused on inventing a safe, inexpensive electric light to replace the gaslight–a challenge that scientists had been grappling with for the last 50 years. Edison set up the Edison Electric Light Company and began research and development. He made a breakthrough in October 1879 with a bulb that used a platinum filament, and in the summer of 1880 hit on carbonized bamboo as a viable alternative for the filament, which proved to be the key to a long-lasting and affordable light bulb. In 1881, he set up an electric light company in New york.

Although the patent described several ways of creating the carbon filament including using “cotton and linen thread, wood splints, papers coiled in various ways,” it was not until several months after the patent was granted that Edison and his team discovered that a carbonized bamboo filament could last over 1200 hours.

THE FIRST INCANDESCENT LIGHT BULB :

Incandescent light bulb use electricity to heat a carbon or metal base filament inside a glass bulb until it becomes hot and emits a radiant glow. A vacuum keeps the filament from burning up too quickly and blackening the interior of the glass bulb. Many of the first incandescent light bulbs faced the same challenges – a poor vacuum design, inferior or expensive filaments, and bulb blackening. However, these early experiments were pivotal in the development of the first commercially viable incandescent light bulb.

Incandescent bulbs are manufactured in a wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external regulating equipment, have low manufacturing cost, and work equally well on either alternating current or direct current. As a result, the incandescent bulb became widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps, and flashlights, and for decorative and advertising lighting.

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