A Look Back at the History of LEDs
As you might have guessed, us here at LampShopOnline are a little bit in love with LEDs, as is the rest of the lighting world! Although they are often attributed to the 1960s, the history of the LED actually stretches back over 100 years, and so we thought we'd take you all the way back to the beginning.
Who's who in the history of LEDs
1907- Henry Joseph Round- A British scientist, Round found that silicon carbide and a 'Cat's Whisker' which is the nickname of a small piece of wire, would light up if a current was run through it. He published his findings, but his research was headed in another direction and this finding was lost. |
1921- Oleg Lossew- He discovered the 'Round Effect' at the same time as Round himself, and did much more detailed studies into Light emitting diodes for over a decade. However, he was Russian nobility in the time of the Bolshevik take over, and so died in 1942 with his work undiscovered. Only recently has his work into LEDs been rediscovered and acknowledged. |
1935- Georges Destriau- Often called the inventor of electroluminescence as he coined the phrase, Destriau called the light a 'Lossew Light'. He published a report on electroluminescence after observing it from zinc sulfide powders. |
1951- The development of the transistor is a huge step forward for semiconductor physics, and for LEDs, as these allowed for the current to flow to create a diode. |
1961- James R. Biard and Gary Pittman- While working at Texas Instruments, they accidentally invented the first infrared LED. |
When LEDs were ready for the market
1962- Nick Holonyak- Called the Father of LEDs, Holonyak was in fact trying to invent a visible LED laser when he created the first visible red luminescent diode. This was the first LED in the visible spectrum and this entered the market in the same year. It was first used as an indicator light in the military. |
1972- M George Craford- A graduate student of Holonyak, Crawford created the first yellow LED, and a brighter red one for more commercial uses. The results of new semi-conductor materials also meant that LEDs now could be in green and orange. |
1972- Herbert Maruska and Jacques Panvoke- Through various experiments, Maruska and Panvoke created the first violet LED which was the foundation for the first true blue LED light. |
1993- Shuji Nakamura- Created the first brilliant blue LED and a more efficient green spectrum range LED, which was the first glimpse that these lights could be a replacement for light sources. |
1995- The 1st LED white light luminescence conversion, and this was launched as a light 2 years later. |
2006- The 1st LED with 100 lumens per Watt is produced. |
The Nobel Prize winners behind blue light-emitting diodes
7th October 2014- Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura were awarded the Nobel Prize in Physics for the invention of the efficient blue light-emitting diodes. This enabled bright, white light which was energy saving and seen as the future of lighting on a mass scale.
What's the future of LEDs?
The future, as ever, is unknowable, but industry seems to be leaning towards understanding controls more, and for using LEDs for more than just light. The Internet of Things is a project which is attempting to make Wi-Fi capable from everyday objects like LED bulbs, leading to other changes, such as up-to-date traffic information from street lights.
There are also OLEDs. These are LEDs with Organic materials, which are materials based around carbon atoms, such as wood and plastics. They're super light, very thin and could be printed onto clothing due to their flexibility. These could become a viable light source in the near future which would be revolutionary due to it's unusual and super versatile nature. Whether this comes true though, we'll have to wait and see.
At LampShopOnline we offer a complete range of LEDs at competitive prices - view the range here.
Sources Used:
http://www.edisontechcenter.org/LED.html
http://www.explainthatstuff.com/how-oleds-and-leps-work.html
Published 2015/09/14