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A Century In The Making: The Long History Of The LED Lightbulb

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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). 

Across the Atlantic, and Half a Century Later…

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. 

And Then There Was Light: The LED Revolution Begins

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.

LEDs Become Commercially Viable

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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  • What Are the Advantages of LED Lights?

    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:

    1. Longevity: On average, the traditional incandescent lightbulb last about 1,000 hours.  A 12-watt LED bulb lasts 25 times longer, or 25,000 hours.
    2. Energy-Efficiency: Incandescent bulbs are about 20 percent energy efficient (meaning about 80% of the energy used is lost through heat), while LED bulbs are 80 percent energy-efficient.
    3. Environmentally-Friendly: Unlike fluorescent bulbs, which contain mercury, LED lights contain no toxic chemicals. They’re also 100 percent recyclable.  Finally, because of their greater energy efficiency, they reduce the average user’s carbon footprint by more than 30%. 
    4. Durability: LED lights are manufactured using durable components that stand up to rugged conditions which would cause incandescent or fluorescent bulbs to fail. They can withstand shocks, vibrations and external impacts, making them the wise choice for outdoor lighting.
    5. No UV Emissions: Because LED lights produce very little UV emissions and very little heat, they’re suitable for use with products that are heat-sensitive. They’re also the better choice for any UV sensitive materials, such as those in archaeological sites, museums and art galleries.
    6. Flexibility: LED lights can be combined in a wide variety of shapes to create highly-efficient illumination. They’re also conducive to dynamic light control and can be used to produce a range of creative lighting effects.
    7. Application-Efficiency: LEDs are able to focus light to specific locations without the aid of reflectors required with traditional lighting. 
    8. Stability: Every time you turn an incandescent bulb on or off, you reduce the number of hours it lasts. This is not true with LED lights.
    9. Less Wattage: A watt is a unit of energy required to create a certain amount of light. While incandescent bulbs typically require 300-500 watts of power, LED lights use just 45-70 watts to operate.


    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