Scientist Shuji Nakamura of the University of California, Santa Barbara shared a Nobel prize with two other winners for an invention that could lead to energy efficient lighting on a global scale; blue light-emiting diodes.
The blue LED creation could potentially be used for lighting workplace premises, homes and in commercial use. By being combined with red and green LEDs or using phosphor to generate white light, which results in a saving up to 10% on electricity bills. In comparison, conventional lightbulbs lose heat because they have to heat up a wire filament, fluorescent lamps fair better but not by much.
With LED however, negative electrons combined with positive ‘holes’ in layers of semi-conductor produce light much more efficiently and scientists have been able to produce both red and green LED through time. Blue light however has continually caused a problem due to the difficulty in growing gallium nitrade crystals that can be encourage to produce the blue light, which with it high visible frequencies is crucial to then producing white light.
Mr Kakamura has been examining the problem for years, working in his own time whilst employed at a Japanese company, Nichia, who considered the project a waste of time. Gradual breakthroughs over periods of years have finally resulted in a solution: growing material on sapphire coated aluminium nitride means that now gallium nitride layers can be modified to carry the positive ‘holes’ need to produce blue lighting.
Mr Kakmura and his two colleagues efforts, at last appreciated, have been described as remarkable and is expected the breakthrough will feature in energy efficient lighting and everyday electronic devices in the future.
In other news on blue LEDs, it appears that insects are more attracted to it than to white and yellow light. Scion, a New Zealand based research institute found that 48% more insects were found in blue light traps than regular sodium vapour bulbs, typically found in street lighting that emit yellow light.
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