How important is a positive blue LED for Nobel Prize 2014?

When the application of LED has become common, not many people understand that the birth of blue LED means what.

>>>Japanese scientist won the 2014 Nobel Prize in Physics

The announcement of the Swedish Nobel Committee on the 2014 Nobel Prize for Physics on October 7 confirmed that the invention of the blue LED of three Japanese scientists was a revolution in projection technology. shining.

Three scientists won the Nobel Prize in 2014.

'They created a revolution. They succeeded when others failed. Incandescent bulbs lit the 20th century, and the 21st century will be lit by LED bulbs , 'the statement said.

The "revolution" that the Nobel Committee mentioned, actually began more than 20 years ago.

LED is an acronym for Light Emitting Diode , which means light emitting diodes , which are diodes capable of emitting light or infrared, ultraviolet rays. Like diodes, LEDs are made of a p-type semiconductor with a n-type semiconductor.

Scientists created LED from the early years of the last century. However, until the 50s of the last century, the first infrared LEDs were actualized.

The first LED to see visible light is the Red LED by Nick Holonyak, Jr. discovered in 1962. So far, Holonyak is still considered the father of LED. Ten years later, George Craford invented the first yellow LED and improved the brightness by 10 times for red LED as well as red-orange LED.

While red LEDs and then green LEDs have been created for a long time, creating blue LEDs is still a challenge for scientists at that time.

It took nearly 30 years for people to overcome this challenge. It was in 1994, when Shuji Nakamura, working at Japan's Nichia Company, first created blue LEDs.

The invention of blue LED has revolutionized lighting technology.

Two key technologies in Shuji Nakamura's invention are the implantation of GaN on the sapphire substrate and the creation of P semiconductor layer from GaN (developed by Isamu Akasaki and H. Amano, two researchers at Nagoya University).

The creation of blue LEDs is extremely important because, due to the lack of this color, it is impossible to create LEDs with white light like the natural light of the sun.

The natural white light we see is essentially a blend of all monochromatic lights. The human eye is only sensitive to the three spectral regions (roughly corresponding to the orange, green and blue areas on the spectrum), so only when blue LEDs are created, one of the three original colors, people can produce white light.

The introduction of blue LEDs along with the invention of high-performance LED one year later officially created white LEDs. Also starting here, new light-emitting diodes (LEDs) formally change the lighting technology.

Today, LED bulbs are widely used in lighting due to their high durability and superior energy saving compared to traditional incandescent bulbs. Comparison shows that the use of LED bulbs save 85% more energy than traditional light bulbs.

In addition, because the size of the LED is very small, they are also widely used in electronics that need high precision, especially the display of TV and phone and many other practical applications.