Osram LED - Astronomy News

Blobrana

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Posts: 131433

Date: Apr 25 02:03 2013

RE: Osram LED	Permalink

New LED Streetlight Design Curbs Light Pollution Streetlights illuminate the night, shining upon roadways and sidewalks across the world, but these ubiquitous elements of the urban environment are notoriously inefficient and major contributors to light pollution that washes out the night sky. Recent innovations in light emitting diodes (LEDs) have improved the energy efficiency of streetlights, but, until now, their glow still wastefully radiated beyond the intended area. A team of researchers from Taiwan and Mexico has developed a new lighting system design that harnesses high-efficiency LEDs and ensures they shine only where theyre needed, sparing surrounding homes and the evening sky from unwanted illumination. The team reported their findings today in the Optical Society's (OSA) open-access journal Optics Express. Read more __________________

Blobrana

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Posts: 131433

Date: Oct 10 15:13 2012

LEDs	Permalink

LED at 50: An illuminating history by the light's inventor The light-emitting diode has brightened our lives for half a century - from lighting up the city streets at night, to decorating Christmas trees each December. Read more __________________

Blobrana

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Posts: 131433

Date: Apr 11 21:14 2007

The LED	Permalink

If you look in an encyclopaedia, the LED was invented by four independent American research groups in 1962. But the latest edition of Nature photonics reveals that it was actually discovered by a little-known Russian genius around 40 years earlier. Oleg Vladimirovich Losev was a radio technician with a fierce talent. In the mid 1920s he noticed that diodes used in radio receivers emitted light when current was passed through them. Then, in 1927, he published details in a Russian journal of the first ever LED. Nikolay Zheludev, at the University of Southampton, has dug up Losev's story. Read more __________________

Blobrana

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Posts: 131433

Date: Sep 11 23:42 2006

White LED	Permalink

A Japanese scientist who invented environmentally friendly sources of light has been awarded this year's Millennium Technology Prize. Professor Shuji Nakamura was given the 1m Euro (£680,000) prize at a ceremony in Helsinki, Finland. The award recognised his inventions of blue, green and white light-emitting diodes (LEDs) and the blue laser diode. White LEDs could provide a sustainable, low-cost alternative to lightbulbs, especially in developing countries. Read more __________________

Blobrana

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Posts: 131433

Date: May 18 01:06 2006

uvLED	Permalink

A trio of Japanese scientists say they have invented an ultraviolet light-emitting diode (LED) that could open the way to a new generation of optical discs with very high data-storage capacity. The LED operates deep in the ultra-violet range of the energy spectrum, with a wavelength of only 210 nanometres (210 billionths of a metre), the shortest of any device of this kind, they report in Thursday's issue of the British journal Nature. LEDs are semiconductors that emit light when they are electrically stimulated. They are widely used in consumer gadgets, providing the light source in many of today's up-market flat-screen televisions. LEDs that emit ultraviolet light, which is not visible to the human eye, could have biological and public-health applications, such as killing germs in contaminated water. They could also eventually replace lasers, which gobble up more energy and use toxic gases, as the tool for reading disc-stored data. Engineers are cramming more and more information on disks, which thus throws down the challenge of finding a source of coherent light that is fine enough to read between ever-tighter tracks of data. To do this, they have been working progressively farther down the light spectrum, from the wider wavelengths of red towards the narrower wavelengths of blue and violet. For instance, the latest industry standard in commercial lasers is Blu-Ray, whose 405-nanometre wavelength enables 27 gigabytes of storage on a single-layer DVD. This compares with ruby lasers, whose wavelength of 4.5 gigabytes enables storage of 4.5 gigabytes. The new LED devised by Yo****aka Taniyasu of NTT Basic Research Laboratories and colleagues is based on "doping" aluminium nitride, a substance not previously used in LEDs, with silicon or magnesium. Source __________________

Blobrana

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Posts: 131433

Date: Apr 13 12:32 2006

Organic LED	Permalink

Scientists from Princeton University, the University of Southern California and the University of Michigan, have managed to get organic light-emitting diode (OLED) to emit sufficient light to illuminate a room. Previous attempts to make OLEDs like this have largely failed to make an impact because traditional phosphorescent blue dyes are very short lived. The new polymer uses a fluorescent blue material instead which lasts much longer and uses less energy. The researchers believe that eventually this material could be 100% efficient, meaning it could be capable of converting all of the electricity to light, without the heat loss associated with traditional bulbs. An organic light-emitting diode (OLED) is a thin-film light-emitting diode (LED) in which the emissive layer is an organic compound. OLED technology is intended primarily as picture elements in practical display devices. These devices promise to be much less costly to fabricate than traditional LCD displays. When the emissive electroluminescent layer is polymeric, varying amounts of OLEDs can be deposited in rows and columns on a screen using simple "printing" methods to create a graphical colour display, for use as television screens, computer displays, portable system screens, and in advertising and information board applications. OLED can now also be used in lighting devices. Read more __________________

Anonymous

Date: Jun 15 01:22 2005

Osram LED	Permalink

Osram has developed the world’s brightest white light-emitting diode. Known as Ostar Lighting, this LED supplies 200 lumens, thus literally putting light bulbs and neon lamps in the shade. Previously, the brightest LED from the Siemens subsidiary Osram had an output of 120 lumens. As far as its luminosity is concerned, Ostar Lighting can therefore compete with conventional lamps. The system has an average service life of 50,000 hours, or almost 18 years if used for eight hours a day. The new LED is currently being prepared for series production and is scheduled for market launch in early 2006. The researchers at Osram Opto Semiconductors in Regensburg achieved this extraordinary level of brightness by channelling almost all of the light that is generated by a semiconductor chip at 700 milliampères to the outside. A number of different techniques were used to accomplish this feat. The chip is coated with a metal reflector and a specially structured, microprismic surface that steer light rays directly upward. The chip radiates blue light that is changed into white light by a second, yellow coating. Because LED technology is still expensive, the extremely bright light-emitting diode will initially be used for special lighting applications such as spotlights, reading lamps, designer lamps and safety lamps. Since the Ostar Lighting system measures only 1 x 3 cm and has an installation depth of six millimetres, it opens up new design opportunities for using LEDs in furniture or buildings, for example. press release __________________

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