Fifty years ago this month, 33-year-old GE scientist Dr. Nick Holonyak, Jr. invented the first practical visible-spectrum light-emitting diode (LED), a device that GE colleagues at the time called ‘the magic one’ because its light, unlike infrared lasers, was visible to the human eye.
In an interview with GE Lighting conducted in his University of Illinois, a now 83-year-old Holonyak recounted the competitive forces that propelled him toward his moment of discovery in a GE lab: “If they can make a laser, I can make a better laser than any of them because I have made this alloy that is in the red-visible. And I am going to be able to see what is going on. And they are stuck in the infrared.”
When Holonyak joined GE’s team of researchers in 1957, GE scientists and engineers were already researching semiconductor applications and building the forerunners of modern diodes called thyristors and rectifiers.
While GE scientist Dr. Robert N. Hall was working toward realising a semiconductor laser in the infrared with GaAs (Gallium arsenide), Holonyak aimed for the visible with GaAsP (Gallium arsenide phosphide).
Hall used polishing to form laser mirrors, while Holonyak tried to form the mirrors by cleaving. On October 9, 1962, with GE colleagues looking on, Holonyak became the first person to operate a visible semiconductor alloy laser – the device that illuminated the first visible LED.
Fifty years removed from Holonyak’s invention, new, robust and long-lasting LEDs have been incorporated to serve as light sources in countless applications ranging from the mundane to mission critical.
“LEDs are literally everywhere,” notes Mary Beth Gotti, manager of the GE Lighting Institute, a teaching facility at GE Lighting’s 100-year-old Nela Park world headquarters in East Cleveland, Ohio.
“LEDs provide lighting in a variety of electronic devices and indicators, including elevator buttons, exit signs, cell and smartphone displays, TVs, PCs, tablet computers, commercial signage, full motion video screens in sports venues, microscopic surgical equipment, railroad crossings and airport taxiway lights. And they are now hitting mainstream lighting applications like parking lots, roadways, accent lighting, general lighting and more.”
Today, LEDs are available in multiple colours, including the bright, white light consumers are used to seeing from their home lighting. LEDs are embraced for their energy savings and long life. They use up to 75% less energy than incandescent sources, last up to 25 times longer than incandescent and halogen light sources and up to three times longer than most CFLs.
They also are cooler to the touch, start instantly, and the compact shape of LEDs allows for smaller, design-forward lighting fixtures, as well as illumination in tight areas.
“Nick Holonyak is a national treasure,” notes Gotti. “His curiosity and drive to explore and invent have inspired thousands of students and countless innovations. It is breathtaking to consider the widespread and profound impact of ‘the magic one’ that Nick Holonyak brought to life 50 years ago.”
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