Look around your home. How many tiny glowing red or green or blue lights do you see indicating power on, messages waiting, fully- or partly charged battery, standby mode or even power off? How many digital clocks are glowing their time of day? Maybe there's even still a VCR flashing 12:00 12:00 12:00.
Those tiny lights are LEDs – light emitting diodes, essentially tiny lasers on a chip, and they were invented exactly 50 years ago today, on October 9-10, 1962.
And 50 years later, LEDs are probably the most ubiquitous technology in our lives other than AC power itself.
LEDs are not merely status lights, though. LEDs provide the light that light-up your LED LCD HDTV. Outside your home, LEDs illuminate everything on your car's dashboard, your turn signal, brake lights and a growing number of headlights. Outside, LED is replacing neon as the sign-illuminating lighting of choice and incandescent bulbs in traffic lights.
And low-power, long-lived LEDs light bulbs are likely to succeed incandescent and fluorescent lights in our home and offices.
Just like the electric light, one man is primarily responsible for the invention of LED – Dr. Nicholas "Nick" Holonyak, Jr., a laser specialist working as a consulting scientist at GE, ironically a company co-founded by Thomas Edison.
LED who and how
I want to tell you all about Dr. Holonyak, who's still leading a fascinating life. At nearly 84, he's still at work at the University of Illinois at Urbana-Champaign, one of the county's most historic and prestigious engineering institutions, as the John Bardeen Chair Professor of Electrical and Computer Engineering and Physics. The position is appropriate – Dr. Holonyak, a U of I alumina and the first student of Dr. Bardeen, the co-inventor of the transistor and the only two-time physics Nobel Prize winner.
But I digress.
More than the story Dr. Holonyak, the story of the LED is illustrative of just how hard science and technology is, and why we ought not take our tech – or any scientific work or assertion – for granted as much as we do.
The development of the LED was, like many technological advances, merely an off-shoot of other work, in this case Dr. Holonyak's work on lasers. In the summer of 1962, his boss at GE wanted him to work on materials to advance laser technology.
But Dr. Holonyak discovered a combination of materials that emitted visible red light (lasers are largely invisible except in the dark or under certain conditions). In a bit of insubordination, Dr. Holonyak decided to pursue this visible red laser course, resulting in the LED.
His work was and is highly technical (as we'll see), but you can watch this short documentary on Dr. Holonyak and the invention of the LED, "A Brilliant Idea."
More than LED
LEDs aren't Dr. Holonyak's only major achievement.
He's also the guy behind the lasers that play our CDs, DVDs and Blu-ray discs (1980).
Ten years after the LED, he developed laser technology now found in many copying machines and laser printers.
In 2000, he also developed the power-adjusting transistor (called p-n-p-n) found in many dimmer switches and power drills.
He's had at least one major discovery or invention in each of the last six decades.
Holonyak's received a pile of other scientific and civilian honors, including awards from each President Bush – the National Medal of Science in 1990 from Bush Sr. and a 2002 National Medal of Technology from George W.
While Dr. Holonyak has been honored as much as any engineer can be honored (we're all waiting for his Nobel Prize), few people know him outside the physics and engineering community. I hope this post will do a bit to change Dr. Holonyak's mainstream anonymity.
Writing is easy. Science is hard.
One of these honors was Dr. Holonyak's election and induction into the Consumer Electronics Hall of Fame in 2006. I am an elector for this organization and write the induction bios, so I had an occasion to correspond with Dr. Holonyak at the time.
When I discovered this LED anniversary was creeping up, I reached out to Dr. Holonyak to get some additional details about his LED work – specifically to get the exact "Eureka!" dates, which are nowhere to be found in any of the published LED invention literature I've perused.
Even though I asked Dr. Holonyak to lay out the climax of his LED discovery in layman's terms, here's his reply:
Thank you for your e-mail (Sept 28). Everyone imagines a special moment for a major new event. But, maybe it's not like that and actually a long story to get there. It's the diode laser (itself a form of LED), and how we get to a laser, that then informs the LED. I learned how to make the red-spectrum III-V alloy GaAsP in 1960-62, and assembled a red GaAsP laser on Oct 9, 1962. And then we ran it (red diode laser) on Oct 10, 1962. As soon as it (the diode laser) blazed red, I knew more or less at once I had a p-n diode "ultimate lamp" (~ 100% quantum efficiency) and that we would eventually go beyond red (and the ubiquitous red GaAsP LED, maybe still being made) and fill the whole spectrum (see, H. Manchester, Reader's Digest, Feb 1963). The modern direct-energy-gap (ke = kh) visible-spectrum III-V alloy diode laser and LED begins in Oct 1962 in Syracuse at GE. Now all high performance diode lasers and LEDs are direct-gap III-V alloys, including the quantum well we put in these devices in 1977.
Those why deny science…
I reproduce Dr. Holonyak's response to illustrate the enormous amount of knowledge and genius behind not only those tiny glowing lights all over your home, but behind every seemingly simple bit of science and technology our lives are dominated and made simpler by.
Our modern life, good or bad, is the result of layer upon layer of scientific discovery and invention dating back to the ancient Greeks, and even earlier.
Each generation takes the work of the previous generation and generations and builds on it to find improvements or new things, the way Dr. Holonyak built his LED based on materials research, and transistor and laser discovery and invention from the generation before.
This millennially-layered evolution of education, research, knowledge and dedicated genius and perseverance is what drives our society forward in all scientific disciplines, from LEDs to advances in medicine to architecture to meteorology to zoology to ecology to paleontology to every –ology and -onomy.
So the next time you feel the urge to blithely critique or dismiss this gadget or that science, think of Dr. Holonyak and what it took to come up with something as seemingly simply as a tiny glowing light.
These folks in the white lab coats and the pocket protectors have forgotten more than we'll ever know about what they're talking about and deserve our respect and admiration.
Thank-you, Dr. Holonyak, and happy anniversary.