LED History 101

By John Paul Quinn | Jul 15, 2011
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"LED" is often used in casual converstion, and most people think they know what these initials stand for. Actally, most people don’t.

So, the critical and practical question is: what do electrical contractors really need to know about the history and development of LED technology in dealing with their customers?

Remember the adage that if somebody asks you what time it is, you shouldn’t tell him how to build a watch. So let’s try to keep it simple.

LED stands for light-emitting diode and refers to a solid-state semiconductor electronic component that gives out various levels and colors of light.

LEDs have been around for a little more than a century. Most historians agree that the first device was crafted in 1907 by Captain H. J. Round, a British radio technology pioneer and a personal assistant to Guglielmo Marconi, who conducted the first transatlantic radio wireless transmission.

In the lab, Round stumbled across electroluminescence, an optical and electrical phenomenon in which a material produces light in response to the passage of electric current or to a strong electric field. After the discovery, he experimented with the first generation of LED devices.

Round continued research into early illumination and communications technology throughout his life, and he holds 117 patents.

However, no one knew exactly what to do with these LEDs. Fast-forward to 1962, where the story takes on an “only in America” spin, and these esoteric LED devices finally get upgraded to practical usefulness.

Working on the railroad
The media, academia and the electrical/electronic community agree that Nick Holonyak Jr., Ph.D., is “the father of the LED.” The son of Eastern European immigrants, Holonyak decided, after a grueling 30-hour shift on the Illinois Central Railroad, that pursuing higher education was preferable to a career in the rail yards. Holonyak earned his bachelor’s, master’s and doctoral degrees in electrical and computer engineering from the University of Illinois in the early 1950s.

In 1962, while working at General Electric Co., he developed the first practically functional visible-spectrum LED device for commercial use. He also invented the semiconductor laser, and co-developed the first dimmer switch, among other things. He holds 41 patents.

Holonyak realized LEDs had the potential, if produced under the proper conditions and with the right chemical compositions, to provide a semiconductor light source for a variety of uses, ranging from high-tech industrial and research applications to aircraft night vision to automobile brake lights.

The consumer press as well as academic journals discovered Holonyak and showcased his work early on. In a 1963 Reader’s Digest article, he forecast with remarkable prescience—and not a little panache—that LED lighting would someday supersede the ubiquitous incandescent light bulb in the American household.

More recently, a 2003 Chicago Tribune article about Holonyak’s achievement states: “The economical and reliable devices critical to DVD players, bar-code readers, and scores of LED-related consumer products today owe their existence in some way to the demanding workload thrust upon one particular Illinois railroad crew decades ago.”

So how does this background information help us today?

Applications and affordability
What do customers need to know about LEDs? The short answer for contractors to give customers is that LEDs are electronic components used in a variety of solutions that are already widely employed in traffic lights and supermarket refrigerator cases and are now increasingly being used for household lighting applications, which is what Holonyak predicted 48 years ago.

This last case is probably the most important potential opportunity for average electrical contractors today.

“LEDs have been around in various specialty product sectors for over a decade,” said Steve Briggs, vice president of global product development at GE Lighting. “But the technology really started to cross over into general illumination about two years ago. The market has evolved tremendously, and there have been advances in LED performance as well as reductions in cost. Initial installation investment is still a consideration at this time.

“But in the home, consumers can now economically replace incandescent and halogen bulbs with LEDs in situations such as down lighting and accent lighting. They are still not suitable for replacing linear fluorescents, which will probably not happen for another few years.”

While LED lighting prices may remain an issue for many individual homeowners, industry observers expect it to change. And, it has already begun. As has been the case with virtually all solid-state products, economies of scale kick in, and price declines as manufacturing volume increases.

“Pricing will continue to decrease starting at the LED component level,” said Steve Landau, director of marketing communications at Philips Lumileds Lighting Co., the parent company’s business unit focusing on developing illumination-grade LEDs as opposed to lower wattage products for signaling and signage.

Part of the problem is that allocation for lighting is often at the bottom of the budgeting food chain. So the contractor might well address the problem of mindset and priorities, not pricing.

“Unfortunately, in too many cases, lighting is left until the end of an installation project,” Landau said. “The contractor and homeowner customer will use whatever budget money is left to buy the lighting materials they can afford. Lighting needs to be treated as a critical part of the project in terms of the desired final objectives.”

And since energy saving is the acknowledged primary objective today for everybody from multinational corporations down to homeowners, serious consideration should be given to LED lighting, which is emerging as the energy-efficient and cost-efficient technology of choice over the long term.

Lumens and laws
The lumens per watt capability of LED lighting continues to improve at a significant pace. Manufacturers agree that in 2001, the best LED source put out 18 lumens, and today, this exceeds 100 lumens. Also, a 60-watt incandescent lamps puts out 800 lumens, while, as an example, the Philips EnduraLED lamp, producing the same lumens, uses only 12.5 watts.

“There are over 400 million 60-watt bulbs sold in this country every year,” Philips’ Landau said. “Swapping out existing incandescent or halogen bulbs for LED lamps makes a lot of sense, even if there is a price differential. Just consider that savings of 47.5 watts per bulb, which goes straight to the user’s bottom line and will have a positive impact on the energy profile of the country.”

Energy and cost savings may be an attractive carrot, but there is also a big legislative stick.

Both in the United States and Europe, regulations are either in place or being enacted that will effectively eliminate the incandescent lamp within the next few years, and may eventually affect CFLs because of their lead and mercury content and the costs related to their proper disposal.

“Any time there is a recycle mandate or a disposal charge, that strengthens the rationale for LED lamps,” GE’s Briggs said. “As this legislation continues to take shape, consumers will seek alternatives to incandescents, with many migrating to CFLs and halogen. But a good portion will go directly to LED.”

Technology takes its own good time in evolving and in winning acceptance. The LED—once only a gleam in Captain Round’s eye, and a ticket out of working on the railroad for Dr. Nick Holonyak—stands a pretty good chance of being the primary lighting source of the 21st century.

QUINN reports on a broad range of business and industry issues for journals in the United States and Europe. He can be reached at 203.323.9850 and [email protected].

About The Author

John Paul Quinn reports on a broad range of business and industry issues for journals in the United States and Europe. He can be reached at 203.323.9850 and [email protected].





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