LED Lights: A Brief Rundown on History and Uses
Light-Emitting Diodes, or LED lights--most of us have heard of them by now, but what makes them so special or significant? What do they do, and what are they used for? Well, because some are speculating that LEDs are "the way of the future," the answers to these questions may be more relevant to you than you might think!
Believe it or not, the first known incident of a solid-state diode emitting light was in 1907 when the English scientist H.J. Round was experimenting in Marconi Labs; he reported that a crystal of silicon carbide emanated an electroluminescence while he was using a cat's-whisker detector (which is a device meant to work with semiconducting crystals).
This report was likely dismissed as a strange anomaly, as was Oleg Vladimirovich Losev's independent creation of an LED over fifteen years later. It was not until 1961 that the scientific community recognized the fact that semiconductor alloys will release infrared rays when exposed to an electric current. This was definitively established that year by Bob Biard and Gary Pittman of Texas Instruments.
Eventually this led to the development of the first red LED light. Within ten years, yellow and brighter red and red-orange lights had been developed. They were initially found to be of great use in alphanumeric displays, so Hewlett-Packard (HP to us) made use of them in some of the earliest models of handheld calculators. However, they were still costly to develop, so they saw few practical applications until years later.
When the technology began to become integrated, they served as replacements for incandescent indicators, mostly in tools that were more of an expensive investment anyway, such as laboratory test equipment. As it became simpler and more efficient to manufacture them, LEDs spread to usage in television sets, telephones, and wristwatches. They had to be used on smaller scales, as they had not yet become bright enough to light up large areas.
It wasn't until recent years that the "white," LED was developed, which came from mixing blue and yellow to make the light appear white, which led to innovations in higher-powered, brighter LEDs.
The great advantage of developing such bright LEDs is that they consume very little power--electricity or otherwise--while still providing plenty of illumination. In the words of the average consumer, "They last FOREVER, man." And the more advanced the technology becomes, the longer they will be able to last.
At the moment, you can find LEDs implements in all the devices previously listed, as well as flashlights, lanterns, Christmas lights, and so on. But with the development of UV LED lights, they can be put to some more unexpected applications: water sterilization, disinfection of materials, or even as a grow light to supplement photosynthesis in plants.
We have only just begun to tap into this wealth of technology, and as we continue to explore its possibilities, we may be amazed by its potential applications!