Celebrating the 50th Anniversary of the LED

LED History - Fifty years ago today, GE scientist Nick Holonyak invented the first practical visible-spectrum light-emitting diode (LED).

On Oct. 9, 1962, GE scientist Nick Holonyak 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.

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 realizing 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.

Watch as Holonyak recounts that fateful day fifty years later.

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 smart phone 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's LEDs

In 2010, GE was the first manufacturer to be given ENERGY STAR® qualification for the A19-shaped (incandescent-shaped), 9-watt LED that was a replacement for the 40-watt incandescent. In early 2013, GE plans to release its LED to replace the 100-watt incandescent. This bulb emits the same brightness as a 100-watt incandescent, using just 27 watts of energy, and can last more than two decades. The bulb will join GE's extensive family of LED bulbs for residential and commercial applications.

Businesses such as Starbucks, Mitchells & Butlers, Next and Marriott believe in the power of Holonyak's invention. They understand LEDs deliver value not just through energy-cost savings. Maintenance-cost savings are significant because LEDs last longer than any other light source. The LED value proposition isn't reserved just for retail giants operating with thousands of locations. Smaller regional grocers and other retail chains, such as Sainsbury's and Iceland Foods, are getting in on the act.

In the commercial setting, GE offers a variety of LED products, including:

Key Features

  • LEDs can use up to 75 percent less energy than incandescent bulbs.
  • Lasts up to 25 times longer than incandescent and halogen light sources, and up to three times longer than most CFLs.
  • Instant start. LEDs do not experience the delayed warm-up associated with CFL bulbs.
  • Small LED chips allow for more compact, design-forward fixtures, as well as the illumination in tight areas.
  • Cooler to the touch.
  • Robust – no filament to break.
  • Most emit light in a specific direction, versus in all directions, but GE's traditionally shaped LED bulbs are omnidirectional. That is, they are designed to emit light all around, just like a standard incandescent light bulb.

The Science Behind LEDs

Nick Holonyak using a GaAsP (Gallium arsenide phosphide) laser, the device that illuminated the first visible LED.

LEDs are small light sources or thin chips that become illuminated by the movement of electrons through a semiconductor material.