We all have heard the term “LED” when it comes to light bulbs, but most don’t actually know what the acronym stands for or how these lights work. So, how does an LED work? LED light is a type of solid-state lighting. Without producing heat, a semiconductor converts electricity into light into (usually) a small area around the size of one square millimeter or less. This space is called the diode. Thus, in an LED lamp, there are actually multiple diodes emitting light. Light is generated and emitted in one direction, which is very helpful because it mitigates the need for any diffusers or reflectors.
It seems like everything is made with LED lights today, from LED flashlights, to household light bulbs, to smart phones. LED stands for “light-emitting diode,” and this technology is the latest and greatest in lighting. It is the most energy efficient method on the market today, which explains why it is utilized so often in commercial and businesses applications.
How LED Came to Be
The invention of the LED light was a slow, and timetimes rocky, process. Back in the year 1907, a man named Henry Joseph Round observed a phenomenon known as electroluminescence in Silicon Carbide. But unfortunately for both Mr. Henry Joseph Round and us, the yellow light his experiment produced was not strong enough to be of any real use. Mr. Round noted then shelved the phenomenon without conducting any further research. Fast forward to 1920, two men named Bernhard Gudden and Robert Wichard Pohl replicated the phenomenon by using Zinc Sulphide and Copper. However, once again, the light yielded from the experiment was too faint to be of any practical use. So, just like Mr. Round, the two scientists wrote down their observations and moved on.
Sixteen years later in 1936, a man named George Destriau published a report detailing the phenomenon of light being produced by Zinc Sulphide powder when running an electric current through it. The phenomenon finally had a name. He coined the term “electroluminescence”.
Finally, in 1961 the ball started rolling today what we now know as LED lights. Two employees at Texas Instrument, Robert Biard and Gary Pittman, invented an infa-red LED. However, there was one small issue. The light was completely invisible to the human eye. There was one good thing to come out of Biard and Pittman’s invention, though. They had created a laser diode.
The First Light-Emitting Diode with Practical Use
A year after the work at Texas Instrument, while working with General Electric, Nick Holonyak, Jr created the very first LED that could produce visible red light. For this achievement decades in the making, Nick Holonyak, Jr was named the “Father of the Light-Emitting Diode.” Has a nice ring to it, doesn’t it?
For the rest of the decade, experimentation on semiconductors continued. Little by little scientists were able to produce more and more efficient LEDs. Initially, LEDs were made with a Gallium Arsenide Phosphide on a Gallium Arsenide substrate, however it was discovered that instead using a Gallium Phosphide as the substrate greatly increased the light efficiency. The red light emitted got brighter and eventually, orange LEDs began to emerge.
After a successful decade of experimenting, a Monsanto Company employee named M. George Craford made the biggest discovery: the color wheel. By using two Gallium Phosphide chips—one red and one green – he was able to produce an LED that emitted a pale yellow light. As it just so happens – Monsanto Company was the first to produce LED lights on a large scale for mass consumption. Craford was able to invent an LED light that emitted a light about ten times brighter than Nick Holonyak, Jr’s LED. Perhaps our good friend M. George Craford deserves a snappy nickname, too – perhaps “Father of the 10x Brighter LED”.
Super-Bright LEDs: First Gen
Scientists during the 1970’s started only exclusively using Gallium Phosphide to make LEDs – this emitted a pale green light and by the end of the decade resulted in an improved version of LED that could produce pure green light. A company by the name of Fairchild Optoelectronics began creating low-cost devices using LEDs and the lights gained great popularity.
After the LEDs big break in the ‘70’s, research and development work on the LED only intensified. Soon, first generations of super-bright yellow, red, and green LEDs emerged in the ‘80’s. By the 90’s, scientists had begun experimenting with the compound Indium Gallium Aluminum Phosphide (try to say that three times fast) and had produced even brighter LED lights. In 1994, prolific inventor Shuji Nakamura invented ultra-bright blue LEDs with Gallium Nitride and soon afterwards, created a high-intensity green and blue LED with the help of the compound Indium Gallium Nitride. The ultra-bright blue LED Nakamura became the foundation for the development of the white LED we’ve all come to know and love today. It’s cost-effectiveness and functionality made it a perfect choice for commercial and manufacturing operations. By coating the blue light-producing chip with fluorescent phosphors, the diode had the capability to emit bright white light. Shuji Nakamura later won the Nobel Prize in Physics in 2014 for this discovery and his singular role in advancing the technology we all use today.
Once the word was out about the white LEDs impressive results, the U.S. Department of Energy saw it as a cost-effective opportunity for business owners to light their work and commercial spaces and greatly encouraged its development. Today, that “encouragement” brought forth the modern LED light. Over 100 years in the making, today’s LED light is seven times more efficient than more traditional incandescent light bulbs and can generate light that lasts 25 times longer while using 80% less energy than their incandescent counterparts. Not too shabby. But, scientists are not ready to hang their hat on this technology yet. Research in the LED continues still. Today, scientists are working to produce a completely pure violet and ultraviolet “black” light. We can’t wait to see what comes next.
Here at Fenix Lighting, we only use the latest LED light technology in our flashlights. This makes them more durable, longer lasting, and more energy efficient than incandescent lights sources. We have some of the very brightest, toughest LED lights on the market. Every single flashlight, headlamp or lantern comes with a full warranty guarantee, meaning that if something were to possibly malfunction with your light’s LED system, our knowledgeable team can get to the root of the problem and repair it. Check out our full inventory of LED-powered lighting solutions.
Sources:
http://www.historyoflighting.net/light-bulb-history/history-of-led/
https://www.electronics-notes.com/articles/history/light-emitting-diode-led/led-history.php