Human-hair sized aluminum foil lamps
Researchers at the University of Illinois at Urbana-Champaign (UIUC) have built 'aluminum foil lamps that outshine incandescent lights.' Their panels of microcavity plasma lamps can contain today 250,000 lamps. These thin panels -- 1 millimeter thick -- are more efficient than incandescent lights and soon will surpass the efficiency of fluorescent lighting. These panels could be used for residential and commercial lighting. They also could be mounted onto curved surfaces, like on the insides of windshields of your cars.
Above is a "cross-sectional diagram of a flat lamp structure based on aluminum foil encapsulated in sapphire and a thin glass coating. The lower right portion of the figure presents photographs at two magnifications of an electrode screen with diamond cross-sectional microcavities. The smallest graduation of the scale is 1 millimeter" (Credit for diagram and caption: UIUC). Here is a link to a larger version.
"Built of aluminum foil, sapphire and small amounts of gas, the panels are less than 1 millimeter thick, and can hang on a wall like picture frames," said Gary Eden, a professor of electrical and computer engineering at UIUC.
Sung-Jin Park, a visiting research scientist at UIUC, added: "Each lamp is approximately the diameter of a human hair. We can pack an array of more than 250,000 lamps into a single panel."
Of course, these scientists claim that these panels will be at the same time inexpensive and energy-efficient: "In the researchers' preliminary plasma lamp experiments, values of the efficiency -- known as luminous efficacy -- of 15 lumens per watt were recorded. Values exceeding 30 lumens per watt are expected when the array design and microcavity phosphor geometry are optimized, Eden said. A typical incandescent light has an efficacy of 10 to 17 lumens per watt."
For more information, this research work will soon be published by the Journal of Physics D: Applied Physics under the name "Lighting from thin (< 1 mm) sheets of microcavity plasma arrays fabricated in AI/Al2O3 glass structures: planar, mercury-free lamps with radiating areas beyond 200 square centimeters." But it's not online yet, and it will not be in the print version of the scientific journal before next month. So visit the journal website if you're interested by this technology.
Sources: University of Illinois at Urbana-Champaign news release, June 4, 2007; and various websites
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