Light-Emitting Diode

What Does Light-Emitting Diode Mean?

A light-emitting diode (LED) is a device that emits light when an electric current passes through it. LEDs first appeared in 1962 as practical electronic components that only emitted low intensity red light. Modern versions can be very bright and are available in a broad spectrum of colors in the visible and even in the ultraviolet and infrared spectrums. They are mainly used in various electronic devices like watches, flashlights, cellphones, displays and many more. Because they have a longer life span and are more energy efficient than regular light bulbs, they have mostly replaced them, especially in household settings.


Techopedia Explains Light-Emitting Diode

The LED emerged from the discovery of electroluminescence by British scientist H.J. Round in Marconi Labs in 1907. Then in 1961, Gary Pittman and Robert Biard conducting experiments at Texas Instruments discovered that gallium arsenide emitted infrared radiation during the application of electrical current; they subsequently patented the infrared LED. The first visible light LED (red) came later in 1962. It developed by Nick Holonyak Jr. while working in General Electric. Holonyak became known as the "father of the light-emitting diode". In1972, M. George Craford, who had been one of Holonyak's students, invented the yellow LED and improved the light output of the red and red-orange LEDs by a factor of 10.

LEDs have a few key advantages over incandescent lights:

  • Most LEDs can be operated with the use of a battery.
  • LEDs are highly efficient because most of the power supplied to them is converted into radiation, thus minimizing the production of heat.
  • When properly installed, they are longer lasting.

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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…