By deploying LED lighting across the board, the United States could save $120 billion – and untold tons of greenhouse gas emissions – over the next two decades. But it's another kind of green that’s keeping the era of the LED from coming to fruition. While scientists have long been able to produce red and blue LED lights, the essential third ingredient for creating good, brilliant white light—green–has proven elusive. But researchers at the National Renewable Energy Laboratory have finally cracked the code on LED green.
Editor's note: A big congratulations today to Theo Gray, whose Gray Matter column was nominated for a 2010 ASME award in the Columns and Commentary category. Great to see Theo's excellent work being recognized. Here, his latest column from the March issue:
The first light-emitting diodes went on sale in 1962, and you could have any kind you wanted as long as it was dim and red. Green, yellow and orange came next, but blue LEDs didn't debut until 1989. So it may surprise you that the first LEDs, discovered in 1907, included blue—and were made of sandpaper.
This 3-D face (left) is built of a swarm of golf-ball-sized, LED-equipped helicopters (right).
Meet the next generation of art installations. Together, the SENSEable City and ARES Labs at MIT have created an adaptable, remote-controlled display comprised of dozens of robotic, flying "smart pixels."
Most houses require hundreds of feet of electrical wire to connect light switches to a main power source, but not my eco-friendly dream home. I’ve installed a wireless lighting system called Verve that uses radio waves instead of copper wiring to command all the lights and outlets in my house. The system not only saves copper (imagine the savings in a skyscraper) but also lets me put switches wherever I want—beside the kids’ beds, in my pocket or even on the dash of my car—without the need to pull out wires or rip up walls.
Graphene may brighten the future more literally than we had originally anticipated, besides merely revolutionizing electronics and Silicon Valley. Swedish and American researchers have transformed the one-atom-thick carbon material into a new, inexpensive lighting component that could give organic light diodes (OLEDs) a run for their money.
Films such as Blade Runner and Minority Report tend to show tons of bright electronic signs blinking or animating frantically from buildings and vehicles alike -- a vision of future Earth that can only become true with much more energy-efficient displays than we have now.
By Dave ProchnowPosted 12.01.2009 at 4:45 pm 6 Comments
Throw out your old wall clock. You’ll be bored with it the moment you’re finished assembling your own persistence-of-vision (POV) clock. Projects based on POV—the phenomenon by which your eye very briefly continues to see an image after it has disappeared—use a moving display to show what looks like a static image. But instead of featuring only a single fixed message, this model shows you the current time on a continuously updated rotating display.
We know, we know: turning a cell phone camera into a microscope isn't exactly a technological breakthrough. In fact, our Best of What's New coverage last year included the CellScope, a cell phone add-on developed at UC Berkeley packing high-powered optics allowing users to transmit images to far-away health centers for diagnosis. But researchers at UCLA have upped the ante, creating a $10, off-the-shelf microscope addition for cell phones that dispenses with the microscope optics altogether.
Even as some of the world moves into a future of unimaginably complex technology, many communities still lack the basic electrical infrastructure needed to power even simply electric devices like light bulbs. Unwilling to wait for the wiring to catch up to the demand, Danish researcher Frederik Krebs has created an LED lamp embedded within a flexible, printable solar panel that could replace the kerosene lamps still used around the developing world.