The history of the LED - CHINA MIRACLE INTERNATIONAL CO., LIMITED

LED Knowledge

The history of the LED

For over 30 years, LEDs have been used in various areas of application, whether for industrial systems, hi-fi equipment, car lights or advertising. LED technical development continues to stride ahead. In the course of recent years, the white LEDs' luminous efficacy has increased to a startling 130 lumens per watt and more. This is a trend that will continue into the future. In addition, the physical effect of electroluminescence was discovered more than 100 years ago.

A short glance back over the history of the LED:
1907	The Englishman Henry Joseph Round discovers that inorganic materials can light up when an electric current is applied. In the same year, he publishes his discovery in the journal "Electrical World". Since, however, he was working mainly on a new direction-finding system for marine transport, this discovery initially is forgotten.
1921	The Russian physicist Oleg Lossew again observes the "Round effect" of light emission. In the succeeding years, from 1927 to 1942, he examined and described this phenomenon in greater detail.
1935	The French physicist Georges Destriau discovers light emission in zinc sulfide. In honor of the Russian physicist, he calls the effect "Lossew light". Today Georges Destriau is credited as the inventor of electroluminescence.
1951	The development of a transistor marks a scientific step forward in semiconductor physics. It is now possible to explain light emission.
1962	The first red luminescence diode (type GaAsP), developed by American Nick Holonyak, enters the market. This first LED in the visible wavelength area marks the birth of the industrially-produced LED.
1971	As a result of the development of new semiconductor materials, LEDs are produced in new colors: green, orange and yellow. The LED's performance and effectiveness continues to improve.
1993	Japanese Shuji Nakamura develops the first brilliant blue LED and a very efficient LED in the green spectrum range (InGaN diode). Some time later he also designs a white LED..
1995	The first LED with white light from luminescence conversion is presented and is launched on the market two years later.
2006	The first light-emitting diodes with 100 lumens per watt are produced. This efficiency can be outmatched only by gas discharge lamps.
2010	LEDs of a certain color with a gigantic luminous efficacy of 250 lumens per watt are already being developed under laboratory conditions. Progress continues to surge ahead.

Pre Page: LED--the technology of the future Next Page: LED: Technology for energy-efficient,...

Product (74)

Special Groups (5)

Company Profiles (2)

CMI Culture (1)

Office&Factory (6)

Certificates (1)

Project Effect (1)

LED Knowledge (8)

News (4)

Credit Report

Products Index

Company Info

LED Knowledge