Mystery of Blue Light Emitting Diode (LED) Solved
Everyone apparently wants to use a DVD player for fun or any needs. A key technology in such an electronic device is a blue light emitting diode (LED).
The market size of the blue LEDs is expected to reach US$10 billion in 2008.
Though this LED was invented in a Japanese company, nobody including those involved in this development knew why the blue LED is possible until recently.
+ + +
The very small lamp, without a bubble and a filament, called an LED has been common in industry for decades due to development of the semiconductor technology.
But, not all types of color were possible with this man-made light emitter. The color of red, green, and so on could be easily realized and their basic theory was well understood. But, it has not been the case with the color blue, though even the blue LED was invented through serious efforts of those involved in this development in a Japanese company.
+ + +
The problem on the blue LED is that a material that emits the blue color has a million times as many structural defects inside as other material for any other color.
With such a great number of structural defects at a level of atoms, it has been thought to be impossible that such a material could emit any light at all; However, it does excellently providing a long-awaited blue light for human beings.
This mystery was recently solved by Japanese researchers.
The material Indium Gallium Nitride (InGaN) has a specific local and minuscule structure where holes, each carrying a positive charge, are effectively trapped so that their energy is converted to light instead of heat.
+ + +
There are two lessons to be learnt here:
First, a defect or a drawback sometimes hides a merit or an asset for a big success.
Secondly, a lucky man who succeeded without knowing why he made it can only find the underlying reason with a help from others so excellent and sympathetic.
"HAVE SOME WINE"