In 1879, Thomas Alva Edison invented the first electric light bulb using a carbon filament, only to receive the patent for his invention two months later. In was the greatest invention of the 19th century, but although the materials used to construct the light bulb changed slightly over the years, its design remained largely unchanged. This is even more surprising, considering that the traditional light bulb is only 5 percent efficient, the rest of the energy being lost through heat radiating in the surrounding medium.
Alternatively, other lighting solutions have been developed to compete with the mighty light bulb, the fluorescent tube being just one of them. It is over 25 percent efficient, and can outlive the light bulb six and a half times. However, they use toxic materials such as phosphor and mercury, which makes them almost impossible to re-cycle.
Currently, most of the population of the world still use the light bulb as a practical lighting solution, in spite of its clear disadvantages. Carbon filaments have been replaced with wolfram, to increase the life span of the bulb and made completely toxic materials free. Now, a company named Group IV Semiconductor is proposing one of the simplest way to make light bulbs more efficient than any other lighting solution available on the market.
Replace the wolfram filament with a silicon one. To be more precise, Group IV Semiconductors suggest that they could replace the wire metal filament with a small computer chip. The solution may look like being very innovative, albeit, in fact, it is extremely old. LEDs have been around for some time now and they have proven their efficiency every time this aspect has been contested. They have way higher electric energy-light conversion ratios, can be easily recycled, have lifespans ten times that of fluorescent tube - meaning 100,000 hours - and, best of all, they can be fashioned to shine basically any color.
These solid state light bulbs also have the advantage of low manufacturing cost and availability of materials. Silicon, the rough material required for creating complex electronic devices, is virtually the dominant element on Earth, aside aluminum.
Group IV approximates that every year the North American continent alone replaces more than 2.2 billion light bulbs, generating a market of 12 billion dollars. Several countries in the EU and around the world even instated law declaring that all light bulbs must be replaced with more efficient lighting solutions by the end of 2010. The main choice remains, for now, fluorescent tubes.
However, there is a slight problem. Solid state light bulbs are rather expensive. Traditional LEDs use, as semiconductor, gallium nitride, while Group IV proposes silicon as semiconductor substance. And here is the problem; silicon is not very good at emitting light while being excited with electrical current as gallium nitride. Group IV says that this could be easily corrected through the implementation of quantum dots within the silicon semiconductor structure and promise a first prototype by the end of 2009, so that, in 2011, the product will go into mass production.