The Science Behind Light Bulbs

More than twenty scientists are known to have individually spearheaded projects toward invention of a working light bulb from the early 1800s through Thomas Alva Edisons success of the late 1870s. Sir Humphry Davy, William Robert Grove, Frederik de Moleyns, W.E. Staite, John Daper, Edward G. Shepard, Heinrich Gobel, C. de Chagny, John T. Way, Alexander de Lodyguine, Joseph Wilson Swan and others could collectively be deemed the Fathers of the Light Bulb, although Edisons efforts resulted in the finally accepted working version. In the pre-Civil War era, the race to create electric light was similar to todays enthusiastic pursuit of Internet technologies. One inventor did not stand alone in lighting concept then, just as one inventor is not solely responsible for the creation of web applications now. But, the reason for Edisons proliferation as the documented inventor of the light bulb is not attributable entirely to his creation, so much as to his scientific process.

Inventing More than Just a Light Bulb
All of the first lighting researchers knew that electricity could be harnessed to create a reliable and convenient light source, but none had combined the right techniques and applications to make history. While others worked diligently to create captured light, Edison stopped to first evaluate their work toward the invention and develop a plan for invention. He was likely most successful and renowned due to this organized approach to the inventive process which garnered more clear and active results.

In chasing electric light, Edison utilized his own creative project management method which included a skilled team, a formal and managed research laboratory, financing, tools and materials in a two-pronged effort of both evaluation of the failures of others and integration of his teams innovation. This approach that Edison created in his quest for a working light bulb is now commonly referred to as research and development, the critical first phase in any major scientific invention process. Edison did not just design a lamp, but drew a road map for inventors to follow in effective creation of new technologies for years to come.

In the active research phase, Edisons lighting research in the 1870s was based upon Sir Humphry Davys proof that heating of thin strips of metal with electric currents created white heat. The white heat illuminated with such verve that Davy realized bigger applications from this harnessing of electricity would follow. He also determined that platinum was key to the lighting process, as the only metal capable of producing the white glow.

Using Davys foundation, Edison initially patented a platinum-based lamp then forged ahead into working on a commercially feasible system that would allow multiple lights to illuminate at once. He saw this as the future of lighting technology, thus was not responsible for merely the invention of a light bulb as he was the creator of larger lighting systems working toward illumination of every aspect of our daily lives. He not only perfected the bulb itself, but also presented the Edison Jumbo generator, the Edison main and feeder and the parallel distribution system. His lack of tunnel vision in approaching development of the optimum light bulb opened many doors toward wider applicability of electric lighting. During his continued efforts toward the bigger picture, his modern light bulb was perfected.

Improvements Upon Advancements of Others
Edisons success and thus attribution of the invention to him was derived from his invention of lamps which included three primary elements other inventors had failed to balance:
Effective incandescence, meaning an efficient and prolonged light source

A higher vacuum than other inventors utilized, critical toward operation and longevity of the lamp

A high resistance lamp mixing a centralized power distribution source with economic feasibility as key to entire lighting systems, wider use of individual lamps, and commercial marketability


Foremost in Edisons work with light and toward effective incandescence was his invention of an optimum filament within the lamp. Filaments provide resistance to the passage of electric currents, sort of harnessing the electricity for illumination. He discovered carbonized cotton thread clamped to platinum wires exceeded the performance of earlier filaments which burned out very quickly. Edisons filament burned continuously for 40 hours. This moved electric lighting a step forward toward commercial viability.

His original working design which burned for several days was modified a number of times then started rolling out through manufacturing mass production. Overall, the creation of Edisons final version was successful through clear evaluation of prior inventors successes and utilization of their advancements as the baseline for innovation in development of his own bulb. As his bulb was being manufactured, marketed, and utilized in buildings throughout the world, Edisons lab continued forward in attempting improvement of his original design. In the 1880s, Edison even discovered that bamboo-derivative filaments burned for up to 1200 hours, a huge improvement over the originally devised 40 hours.

Modern Bulbs and Processes
Now referred to as incandescent light bulbs, todays versions have not vastly changed from Thomas Edisons originals. Modern bulbs utilize tungsten filaments and various gases for heating to higher temperatures. These subtle upgrades have resulted in higher efficiency and brighter illumination, as well as wider applicability for varied use.

Innovation within lighting is no longer about improving the incandescent bulb. Now is a time of developing bulbs for different uses, longer life, greater efficiency, and less impact upon the environment, still using Edisons approach to organized scientific research and development. Some types of modern bulbs are:
Fluorescents glass tubes utilizing mercury vapor and argon gas and phosphor internal coating create higher efficiency, lower heat light

Mercury vapor lamps a version of the fluorescent, utilizing a quartz arc tube containing mercury vapor at high pressure within a protective glass bulb

Neon glass tubes filled with neon gas mixed to create color variations, used for signage

Metal halide Similar in construction to the mercury vapor lamps but create a more natural color balance, used for lighting of large outdoor venues such as stadiums and highways

High pressure sodium similar to mercury vapor lamps but the arc tube is constructed of aluminum oxide in lieu of quartz and contains sodium and mercury solids versus mercury vapor

LED lights very small bulbs that fit directly into the electrical circuit, powered by movement of electrons in a diode


New light-emitting diode bulbs (LEDs) produce very bright light on very little electric energy, last up to 60 years, are 12 times more efficient than tungsten bulbs and three times more efficient than fluorescents. Unlike other versions of efficient bulbs, LEDs light instantaneously rather than requiring a flicker phase into full illumination. Even more encouraging is that they do not contain or use mercury, which is very toxic to the environment in disposal of light bulbs. Household-use LEDs are expected to start replacing regular incandescent bulbs in 2011 as the most major advancement to lighting science since the work of Edison, himself.

As lighting technology moves into a new realm of higher efficiency and environmental sustainability, Edisons original bulb components and shape will soon become distant memory. A bulb the size of a human thumbnail will light spaces as brightly as an older incandescent the size of an entire adult hand, but with greater efficiency, less damage to the environment, and for an entire human lifetime.

Thomas Edison would likely be pleased regarding all of these improvements. However, possibly most important from the invention of his light bulb is his structured research process through which all major technologies since have been founded. It is no wonder that a light bulb turning on over ones head is the commonly accepted artistic illustration of a great idea. After all, in crafting the science of the light bulb, Thomas Edison actually created the science of innovation.


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