From walkways to operating rooms, there is a new kind of lighting that advocates say will help the globe see its way to a more energy sensible future.
Officials in Poughkeepsie announced last week that the Walkway Over the Hudson pedestrian bridge scheduled to open up on the first weekend of October will be illuminated by electron-managing light emitting diodes, commonly called LEDs.
They are strung together and contained in a tubular one-inch diameter shell that is both the lighting instrument and its conduit, said Andy Neal, president of ANL Ltd., a Salt Point-based developer of Illuma lighting systems.
“We literally have two wires on this enormous structure,” said Neal, saying the Walkway lighting “is a very early iteration of the design and its perfect for this illumination need. It”™s just going to be very unique, very much like the bridge itself.”
But lighting of pedestrian walkways is only one use of LED lighting. John Mangiardi, CEO of Greenwich, Conn.-based Optimus Services L.L.C., is patenting an LED-based ambient lighting system for use in hospital operating rooms, with the goal of providing a calming effect for patients and staff in an environment that, by design, is a study in light management.
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Mangiardi envisions such systems in use in modernized operating rooms Optimus has designed for institutions like New York Presbyterian Hospital.
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Light-emitting diodes, also termed solid-state lighting, are semiconductor chips that release light by allowing electrons to fall into “holes” in other atoms lacking that electron. Chips can be doped to produce desired colors.
While expensive to produce, LEDs offer advantages over traditional incandescent bulbs in that they require lower amounts of energy; last longer; can be adjusted to design needs; and can produce a range of colors, including simulating sunlight.
Newer LEDs can last as long as 25,000 hours ”“ or three years burning continuously ”“ according to the Lighting Research Center at Rensselaer Polytechnic Institute in Troy, compared with 6,000 to 10,000 hours for a fluorescent lamp and a mere 750 hours for a traditional incandescent bulb.
Fairfield-based General Electric Co. is producing LEDs for a wide range of applications today, including outdoor lighting and box signs.
Just last week, Holiday Inn purchased 3,200 GE Tetra LED systems as it re-brands its hotels with new illuminated signs, including at seven hotels it operates in Fairfield County, Conn. Holiday Inn expects to cut energy usage by more than half for signs lit an average of 12 hours per day. That represents an estimated reduction of 8,700 metric tons of carbon dioxide annually or the equivalent of planting more than 2,300 acres of trees per year, the company reports.
And AT&T Inc. recently bought 6,500 GE Tetra LED signs that use a stunning 2.6 million LEDs as part of its own re-branding effort.
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GE is also in the chase to develop organic LEDs, whose flexibility makes them coveted for a range of off-the-wall applications like illuminated clothing or wallpaper.
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The Branford-based North American headquarters of Oxley Inc. sells LEDs for use in military tents.
Chemists at the University of Connecticut have been studying ways to increase the luminescence efficiency of single-walled carbon nanotubes, with possible applications for use in LEDs.
And at Yale University, scientists discovered that LED lights used in insect traps captured up to half as many more bugs than those that used traditional bulbs.
According to IMS Research, the top three producers of LED chips today are Japan-based Nichia Corp., Germany-based Osram Opto Semiconductors GmbH, and the Sunnyvale, Calif.-based Philips Lumileds Lighting Co. division of Dutch conglomerate Philips, which has an office in Stamford.
Another supplier, Durham, N.C.-based Cree Inc., built its LED business in part by acquiring related technology from ATMI Inc., which has its U.S. headquarters in Wilton.
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Perhaps the most visible examples of LED signs in Fairfield County are the road signs that greet patrons and passersby of Stew Leonard”™s Inc. grocery stores in Norwalk and Danbury, which flash specials and even videos.
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Bridgeport-based Trans Lux Corp. relies on LEDs for electronic signs it designs for various applications.
But the technology increasingly is being embedded in everyday devices ”“ the city of Stamford is installing LED traffic signals.
And back at Poughkeepsie, the pedestrian crossing 212 feet over the Hudson River leading to Highland will offer an opportunity to see a different kind of lighting, the night sky, said Fred Schaeffer, chairman of the Walkway Over the Hudson committee.
“I think people re really going to love it,” said Schaeffer, who has already been up there under the night sky. “It”™s gorgeous up there.”
The former rail bridge, which opens with much fanfare next month, is the largest element of the Henry Hudson quadricentennial celebration.