Let’s celebrate the 50th anniversary of the LED!
Half a century ago today, Nick Holonyak Jr. introduced us all to the visible Light Emitting Diode (LED). This electronic component has since become an important innovation, used in everything from car headlights to computer monitors.
When I wake up in the morning, my alarm clock has LED lights. my television has LED back lighting, and the PS Vita in my pocket has an OLED screen. The family car has LED headlights and dashboard illumination, and the traffic lights in the city use LEDs as well. The Light Emitting Diode is everywhere, and there's good reason for it; it's powerful, cheap and lasts long. But as widespread as it's use is today, it hasn't been around for all that long: Today is the 50th anniversary of it's introduction.
Thank Mr. Holonyak for your Christmas lights
In 1962, Nick Holonyak Jr, who was working for General Electric, demonstrated the very first visible light LED to the world. The LED was not a new invention at this point; electroluminesance, as a scientific phenomena, was first discovered in 1907. However, up until 1962, LEDs had only been known to be detectable in infra-red wavelengths, invisible to the human eye. Researchers at the GE Advanced Semiconductor lab had been working on a way to make LEDs shine in the visible spectrum in an attempt to find a more energy efficient light source than regular, incandescent light bulbs.
Holonyak's idea for a visible LED was to replace the materials used for making the diode; opting for a mixture of gallium arsenide and gallium phosphide, as opposed to the standard gallium antimonide, indium phosphide and silicon germanium construction. Most of his colleagues didn't believe this technique would work and his idea was dismissed, quite vocally. Lucky for us all, he didn't give up and eventually succeeded, creating a dimply glowing red LED and ushering in a new era of lighting.