An illuminating solution to an electromagnetic problem
What are LEDs?
On Jan. 27, 1880, Thomas Edison was granted U.S. patent 223,898, for an electric lamp using “a carbon filament or strip coiled and connected to platina contact wires.” While this description might not be in line with what most consider to be an incandescent light bulb, it’s essential to consider that light bulbs—indeed, light sources—have been changed and adapted over time. Of course, Thomas Edison never invented the light bulb—neither did Nikola Tesla nor Joseph Swan. The light bulb, in a number of forms, has been invented and reinvented thank to centuries of technological and scientific growth.
The light-emitting diode (LED) is yet another invention that was invented and reinvented over decades of growth in the electrical engineering field. However, the LED as we know it was patented on Dec. 20, 1966. LEDs, in their most basic form, are sources of light produced by energized semiconductors.
How do LEDs work?
Introductory science courses explain that LEDs work through the movement of electrons through a semiconductor material within the LED casing. LEDs contain a cathode and an anode—a positive and negative end, respectively. Electrons flow from the negative to the positive end of a circuit, and an LED is no different. The actual light that’s emitted from an LED is a result of the flow of electrons through the material.
[pullquote align=”left” cite=”” link=”” color=”” class=”” size=””]…a light source that is so energy-efficient is a great necessity.[/pullquote]
What makes LEDs so incredible—indeed, what makes LEDs so much more useful than incandescent and even fluorescent light sources—is the low amount of heat, in relation to the high amount of energy, that is generated by their activation. Coupled with the fact that typical LEDs last for approximately 50,000 hours—a value that is almost 50 times longer than incandescent light bulbs, 20 to 25 times longer than halogen light bulbs, and even eight to 10 times longer than a fluorescent light bulb—one should be able to easily understand why LEDs are scientific marvels.
Why are LEDs important?
In terms of light production, it goes without saying that LEDs are the best commercially light sources available for human consumption. Outside of catching and breeding bioluminescent animals and holding them captive, LEDs are the most efficient sources of manmade light. White light LEDs—diodes that emit light that appears white on the electromagnetic spectrum—is one of the most efficient kinds of light sources, when measuring the amount of energy required to create light in comparison to how much light is actually produced.
However, LEDs are more than just small bits of light that are useful for Christmas decoration. LEDs are found in everything from televisions to laptops to remote controls and even smartphones and tablets. Their ubiquity is a direct result of their usefulness, and their presence in modern electronics is no small accident.
What is the future of LEDs?
The 2014 Nobel Prize for Physics was awarded to Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura for “the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources.”
The research of Drs. Akasaki, Amano, and Nakamura is revolutionary because, through the application of blue LEDS, almost pure white light could be created. White LED lamps are not only far more energy-efficient than normal LEDs, but they are also significantly more longer-lasting. Human energy consumption is widespread and varied, but when one-fourth of the world’s electricity is consumed for light purposes, the invention of a light source that is so energy-efficient is a great necessity.
Furthermore, white LED lamps are so energy-efficient that they can be easily charged and maintained by cheap, local solar power.
The future of LEDs might not be incredibly exciting, but for members of the developing world, their invention is a sign of bright and promising future.