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The year was 1907. Researchers on opposite sides of Europe were looking for alternative means of creating artificial light. In Great Britain, Henry Joseph Round sent 10 volts of electricity into a silicon carbide crystal, emitting a dim, yellowish light. A thousand miles away in Russia, another researcher, Oleg Vladimirovich, replicated Round’s experiment, obtaining the same result, which he described in a subsequent publication as a “light-emitting diode” (LED).
Little scientific research was conducted to augment the work of Round and Vladimirovich for the next 50 years. Then, in 1955 at Radio Corporation of America, another scientist, Rubin Braunstein, continued experimentation with diodes, noting their capacity to emit infrared light. Six years later at Texas Instruments, scientists Gary Pittman and Bob Biard discovered the capacity of the gallium-arsenide diode to produce infrared light when an electrical current was run through it. They were granted the first patent for an infrared LED light for their efforts.
The work of Braunstein, Pittman and Biard represented an important step forward, but the applications of their research were limited, since infrared light is not part of the visible light spectrum. All that changed just seven years later when Nick Holonyak Jr., a scientist with General Electric, succeeded in creating the first light-emitting diode which produced visible light. A decade later, M. George Craford, a graduate student who had studied with Holonyak, moved his work forward by creating both a brighter red LED and the first yellow LED.
The combined work of Holonyak, Craford and other scientists created a reliable source of visible light, but like many scientific breakthroughs, LEDs were still prohibitively expensive.
In those early days of LEDs, the price of LED lights was high, making them appropriate only for limited use. Throughout the 1970s, however, scientists at Fairchild Semiconductors found that using a planar process to create LED semiconductor chips substantially reduced production costs. They reduced the cost from $200 per LED to 5 cents per LED. This ability to manufacture LED lights cost-effectively meant LEDs could now replace incandescent and neon lights and be successfully used in large RGB screen displays, calculators, watches and flashlights.
The rest, as they say, is history.
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LED lights are unequivocally the cleanest and most energy efficient lighting source currently available, and the price for them continues to drop. Prices for LED lightbulbs have decreased a whopping 90 percent in the last decade, according to Think Progress.
They go on to note that within a decade LED lights will save U.S. consumers $20 billion a year and lower CO2 emissions in this country by 100 million metric tons a year. Clearly, the advantages of LED lights are increasingly making it the smart choice for informed consumers and cost-conscious businesses.
Other key advantages of LEDs include:
Have you considered all your options when it comes to saving money with your lighting? Check out our latest infographic to learn more.
Posted: October 27, 2017