LEDs first entered the public consciousness thanks to U.S. researchers who published groundbreaking work in 1962: That was the year four independent groups, from IBM, MIT, and General Electric, reported the achievement of a functional LED semiconductor laser. Although the Russian physicist Oleg Losev was first to write extensively about the underlying science, it was these diverse groups that brought the LED light to North America.
The researchers could not have known just how profound their discovery would prove to be. Indeed, for decades after that milestone, the full potential of the LED was unrealized. LEDs were deployed as indicator lights, accent lighting, and under-shelf illumination, for example. It was not until very recently that many powerful applications were widely adopted.
LEDs Come into Their Own in Countless Applications
The first, of course, was general purpose lighting. Another example, with more far-reaching applications, is the use of LEDs in today’s complex fiber optic networks. Because light does not experience the same degradation conventional electrical signals do, LEDs may be the key to high speed transmissions across oceans and continents. Before LEDs projected light across the ocean, however, they were showing up in much smaller electronic devices. Today, they are used virtually everywhere.
The properties of LEDs make them efficient components for top-quality machine vision and imaging systems – they are increasingly incorporated into drones and industrial inspection equipment that must achieve high bandwidth transmission with a minimal footprint.
When integrated into circuit boards, LEDs stand out for a number of reasons:
- They are small.
- They provide high radiance.
- They rarely need replacement.
- They can be modulated quickly.
Thanks to these traits, LEDs are highly efficient and cost-effective. They have been used in all kinds of advanced electronic systems, pushing the boundaries of what is possible by breaking transmission bottlenecks that were once taken for granted. You can find them in clocks, remote controls, televisions, and much more.
The Science Behind the LED: An Overview
To understand the potential of the light-emitting diode, it’s important to explore the science. Unlike other conventional light sources, LEDs do not have a filament and do not generate excessive heat. Much less energy is lost to heat and more light is produced compared to a common incandescent bulb.
In place of a filament, LEDs are illuminated by the flow of electrons across a semi-conductive material. Under ordinary usage they last thousands of hours longer than a common light bulb, and have a lifespan about equal to that of a transistor. Since a diode is the simplest form of semiconductor, there are no moving parts to produce mechanical wear.
Most LEDs use aluminum-gallium-arsenide as the semiconductor material. This option has been embraced for most applications because it absorbs a relatively small portion of emitted light compared to other semi-conductive materials. Advances in material science, especially on the nano-scale, may soon surpass it, however.
Virtually all aspects of modern electronics have been touched by the LED, and its influence shows no sign of waning. Across many industries, it is one of the unsung heroes of today’s technology.