News tagged with led
Leap Motion creates finger-happy gesture control (w/ Video)
(Phys.org) -- Developers and end users both have been indicating they are ready to start saying long goodbyes to mouse and keyboard. In this touchscreen generation of mobile users, the big stir among gadget ...
Technology / Hi Tech & Innovation
May 23, 2012 |
4.6 / 5 (9) |
10
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Scientists track your carbon footprint, step by step
If you're driving your SUV to the farmers market to buy local asparagus and thinking you're making a difference for the planet, - not so fast. You're focused on a detail and ignoring the gas-hogging elephant in the room.
May 21, 2012 |
5 / 5 (2) |
1
LEDs on silicon can reduce production costs
A new manufacturing technology is expected to greatly reduce the cost of light-emitting diodes (LEDs) in the future. For the first time ever, researchers at the Siemens subsidiary Osram Opto Semiconductors ...
May 21, 2012 |
4.4 / 5 (8) |
0
Mini-projector for smartphones
Their very small displays sometimes make smartphones diffi cult to operate. In the future, a projector will help: if the cell phone is standing on a table, for instance, it can project a large-format display ...
Technology / Hi Tech & Innovation
May 10, 2012 |
not rated yet |
1
Electrical engineers develop LED 'Magic Wands'
Engineers from the University of Bristol have developed illuminating ‘magic wands’ that work by picking up radio signals from mobile devices. The wands, to be showcased on BBC’s Bang Goes the ...
Apr 17, 2012 |
5 / 5 (1) |
0
Virtual blue skies brighten the office of the future
There is light at hand for those who toil away in a poorly-lit office. Scientists at the CeBIT high-tech fair have developed a system that gives the feeling of working outside under blue skies.
Technology / Hi Tech & Innovation
Mar 06, 2012 |
1 / 5 (1) |
3
LED's efficiency exceeds 100%
(PhysOrg.com) -- For the first time, researchers have demonstrated that an LED can emit more optical power than the electrical power it consumes. Although scientifically intriguing, the results won’t ...
Mar 05, 2012 |
4.4 / 5 (65) |
60
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Samsung commits to LED screens, will spin off LCD unit
Samsung Electronics Co. is spinning off its LCD display manufacturing business and merging with its smaller LED display unit in a move that reveals the company's vision of the future of televisions and mobile screens.
Feb 21, 2012 |
not rated yet |
0
Researchers combine mobile phone technology and microscopy
VTT Technical Research Centre of Finland has developed an optical accessory that turns an ordinary camera phone into a high-resolution microscope. The device is accurate to one hundredth of a millimetre. Among those who will ...
Feb 15, 2012 |
5 / 5 (1) |
1
Soraa LED light may dim 50-watt halogen rivals
(PhysOrg.com) -- Soraa, a Fremont, California company founded in 2008, this week launched its first product, a light that uses LEDS (light emitting diodes). The "Soraa LED MR16 lamp" is the "perfect" replacement ...
Feb 09, 2012 |
4.4 / 5 (27) |
24
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All set and ready to glow
A new technique that paves the way for manufacturing affordable LED light bulbs is to be exploited in the UK, in a deal that researchers say could have a dramatic impact on carbon emissions.
Technology / Energy & Green Tech
Feb 07, 2012 |
5 / 5 (1) |
1
LED lights point shoppers in the right direction
Looking for an item in a large department store or mall can be like searching for a needle in a haystack, but that could change thanks to a hybrid location-identification system that uses radio frequency transmitters and ...
Jan 26, 2012 |
2 / 5 (2) |
0
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Philips develops efficient solar powered LED street lighting
Philips has developed what is said to be the world’s most efficient and cost effective solar powered LED street lighting solution per km of road.
Technology / Energy & Green Tech
Jan 24, 2012 |
4.4 / 5 (7) |
8
'Meating' a solution: Research finds that LED lights extend meat shelf life, save retailers money
A switch to LED lights in refrigeration units could save the retail meat industry millions of dollars each year, according to research from Kansas State University.
Jan 17, 2012 |
4.8 / 5 (5) |
0
Sony's next-generation 55-inch 'Crystal LED Display' prototype presented at CES
Sony announced that it has developed the next-generation self-emitting display, “Crystal LED Display,” and presents a Full HD, 55-inch prototype model at the 2012 International Consumer Electronics ...
Electronics / Consumer & Gadgets
Jan 11, 2012 |
5 / 5 (3) |
2
Light-emitting diode
A light-emitting diode (LED) (pronounced /ˌɛliːˈdiː/, or just /lɛd/), is an electronic light source. The LED was first invented in Russia in the 1920s, and introduced in America as a practical electronic component in 1962. Oleg Vladimirovich Losev was a radio technician who noticed that diodes used in radio receivers emitted light when current was passed through them. In 1927, he published details in a Russian journal of the first ever LED.
All early devices emitted low-intensity red light, but modern LEDs are available across the visible, ultraviolet and infra red wavelengths, with very high brightness.
LEDs are based on the semiconductor diode. When the diode is forward biased (switched on), electrons are able to recombine with holes and energy is released in the form of light. This effect is called electroluminescence and the color of the light is determined by the energy gap of the semiconductor. The LED is usually small in area (less than 1 mm2) with integrated optical components to shape its radiation pattern and assist in reflection.
LEDs present many advantages over traditional light sources including lower energy consumption, longer lifetime, improved robustness, smaller size and faster switching. However, they are relatively expensive and require more precise current and heat management than traditional light sources.
Applications of LEDs are diverse. They are used as low-energy indicators but also for replacements for traditional light sources in general lighting and automotive lighting. The compact size of LEDs has allowed new text and video displays and sensors to be developed, while their high switching rates are useful in communications technology.
For more information about Light-emitting diode, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
