LinkNotes: LED

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2012-04-25

Berkeley's Highly Efficient Solar Cells also act like LEDs

New solar cell creates more electricity by lighting up - TECH.BLORGE.com

While solar cell efficiency is theoretically able to reach 33.5 percent efficiency, so far solar cells have only been able to reach 26 percent until now. Eli Yablonovitch, principal researcher and UC Berkeley professor of electrical engineering has developed a new solar cell that will achieve 28.3 percent efficiency and it does so by emitting light.

Source: New solar cell creates more electricity by lighting up - TECH.BLORGE.com

Berkeley Lab Research Sparks Record-Breaking Solar Cell Performances « Berkeley Lab News Center

“A great solar cell also needs to be a great Light Emitting Diode,” says Eli Yablonovitch, the Berkeley Lab electrical engineer who led this research. “This is counter-intuitive. Why should a solar cell be emitting photons? What we demonstrated is that the better a solar cell is at emitting photons, the higher its voltage and the greater the efficiency it can produce.”

Source: Berkeley Lab Research Sparks Record-Breaking Solar Cell Performances « Berkeley Lab News Center

LED-like Solar Cell Absorbs, Emits Light (photonics.com | Apr 2012 | Research & Technology)

Eli Yablonovitch and Owen Miller of UC Berkeley worked out the theory for the new solar cell efficiency. The monitor in the picture illustrates the new physics concept where increased light emission yields higher efficiency. (Image: Eli Yablonovitch)

“Fundamentally, it’s because there’s a thermodynamic link between absorption and emission,” said Owen Miller, a graduate student at UC Berkeley and a member of Yablonovitch’s group.

Designing solar cells to emit light, so that photons do not become “lost” within a cell, has the natural effect of increasing the voltage produced.

“If you have a solar cell that is a good emitter of light, it also makes it produce a higher voltage,” which would increase the amount of electrical energy that can be harvested from the cell for each unit of sunlight, Miller said.

Source: LED-like Solar Cell Absorbs, Emits Light (photonics.com | Apr 2012 | Research & Technology)

KW17 | UC Berkeley unveils LED-type PV cell - SolarServer

Prototype efficiency jumps from 26% to 28.3%

Alta Devices, co-founded by Yablonovitch, used the new concept to create a prototype solar cell made of gallium arsenide (GaAs), a material often used to make solar cells in satellites. The prototype broke the record, jumping from 26% to 28.3% efficiency.

The company achieved this milestone, in part, by designing the cell to allow light to escape as easily as possible from the cell – using techniques that include, for example, increasing the reflectivity of the rear mirror, which sends incoming photons back out through the front of the device.

Source: KW17 | UC Berkeley unveils LED-type PV cell - SolarServer

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2011-11-17

Ultrafast Nanoscale LED Data Transmission Developed at Stanford

New lightning-fast, efficient nanoscale data transmission developed at Stanford | Stanford Engineering

A team at Stanford's School of Engineering has demonstrated an ultrafast nanoscale light-emitting diode (LED) that is orders of magnitude lower in power consumption than today's laser-based systems and is able to transmit data at the very rapid rate of 10 billion bits per second. The researchers say it is a major step forward in providing a practical ultrafast, low-power light source for on-chip data transmission.

Stanford's Jelena Vuckovic, an associate professor of electrical engineering, and Gary Shambat, a doctoral candidate in electrical engineering, announced their device in a research paper set to be published Tuesday in the journal Nature Communications.

Source: New lightning-fast, efficient nanoscale data transmission developed at Stanford | Stanford Engineering

Tests show that the device, technically called "nanoscale single-mode LED," can transmit information in computers from chip to chip at least 10 times the speed of any current computer while consuming more than a 1,000 times less energy, the developers say.

The tiny device is a highly advanced version of the LED lamps that are increasingly used in everything from pocket flashlights and home lighting to the "grow-lights" that force-feed everything from house plants to marijuana farms.

Source: Stanford develops super-fast computer device

Engineers use nanophotonics to reshape on-chip computer data transmission

This illustration shows how a single nanophotonic single-mode LED is constructed. (Image: Gary Shambat, Stanford School of Engineering)

The LED in question is a "single-mode LED," a special type of diode that emits light more or less at a single wavelength, very similar to a laser.

"Traditionally, engineers have thought only lasers can communicate at high data rates and ultralow power," said Shambat. "Our nanophotonic, single-mode LED can perform all the same tasks as lasers, but at much lower power."

Source: Engineers use nanophotonics to reshape on-chip computer data transmission

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2011-01-22

Fraunhofer's Micro Nano Array Projectors

Nanoworld in color

Press Release 20.01.2011

Microscopically small nanostructured arrays of lenses that can record or project amazingly sharp images in brilliant colors are being demonstrated by Fraunhofer research scientists at the nano tech 2011 trade show in Tokyo from February 16 to 18.

[...]

The image illuminating the wall of the Fraunhofer exhibition stand at nano tech 2011 will be produced by a luminous cube. The prototype of the new projector consists of an optical system just eleven millimeters square and three millimeters thick through which a powerful LED lamp shines. The images are amazingly sharp, the colors brilliant – all thanks to micro and nanotechnology. "The special thing about the new projection technology is that the image is already integrated in the microoptics. The pixels measuring just a hundred nanometers or so are stored in a chromium layer under the lens array. Such a microarray has around 250 microlenses, and under each lens there is a microimage. When all of them are projected onto the wall together, a high-quality complete image is produced from an extremely small projector," explains Marcel Sieler, physicist at the Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena.

Collected from: Nanoworld in color – Fraunhofer-Gesellschaft

Mini-projectors – maximum performance

Research News Special Edition May 2010

[...]

In all current systems of pocket projectors, a single imaging channel is used. This means a minimal size for the projector is a given – and smaller will not work. Except for Marcel Sieler: His construction method relies on a number of regularly ordered micro-lenses – an array – as the projection lens. Thanks to the many channels, the construction length of the entire system can be clearly reduced, without impeding luminosity. A high-performance LED is used as the light source.

Collected from: Mini-projectors – maximum performance - Research-News-Special-Edition-05-2010-Topic 5 – Fraunhofer-Gesellschaft

Prototype projector still shines through in sun-lit rooms | News | The Engineer

The technology was inspired by a device known as a fly’s eye condenser used to smooth out beams of light from LEDs. The Fraunhofer team had to design a very precisely arranged array of aspheric lenses designed with a specific shape.

The array is created from a glass wafer with moulded micro-optics on either side. ‘You put a liquid monomer layer on top of the glass and press a negative tool into it and it’s polymerised to get the perfect shape for the microlenses,’ said Sieler.

As well as the basic proof-of-concept model, the team have also used the technology to create prototypes of a larger projector for advertising and illumination, a video graphics array (VGA) camera, and a video projector that takes images from a micro-LCD display.

The team is now seeking industrial partners to help commercialise the devices and Sieler estimates that it is likely to be five years before they are available to buy.

Collected from: Prototype projector still shines through in sun-lit rooms | News | The Engineer

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2009-09-03

Augmented Reality in a Contact Lens

clipped from www.telegraph.co.uk

Augmented reality: a technology whose time has come

Picture this: you’re sightseeing in London and stop at the Houses of Parliament. You want to know more about its history, where you can get a cup of tea and you need to find out how the Tube is running before you continue your tour.

“Augmented reality goggles would be one obvious solution,” says Pearson. “But already the technology is moving beyond that. Within the next few years, it’s possible that scientists will have created a contact lens that also doubles as a nano display, literally allowing us to view an augmented reality through our own eyes.”

Researchers at the University of Washington have already created a prototype contact lens and the US military’s Defense Advanced Research Projects Agency is working on contact-lens displays that could provide battlefield combat data.

clipped from spectrum.ieee.org

Augmented Reality in a Contact Lens

A new generation of contact lenses built with very small circuits and LEDs promises bionic eyesight

clipped from spectrum.ieee.org

In this lens concept, an antenna at the periphery collects incoming RF energy from a separate portable transmitter. Power-conversion circuitry provides DC power to other parts of the system and sends instructions to the display control circuit. The display, at the center, might consist of LEDs, which would turn on and off, or LCD-like elements, whose transparency would be modulated by the control circuit. An energy-storage module, perhaps a large capacitor, is connected to a solar cell, which could provide a boost to the lens. A biosensor samples the surface of the cornea, performs an analysis, and provides data to the telecommunication module to transmit to an external computer.

clipped from www.dailymotion.com

clipped from www.ee.washington.edu

Babak Amir Parviz

Sources:

Sanyo's Eneloop Lamp

clipped from news.cnet.com

Sanyo's Eneloop Lamp: The flashlight that heals?

Sanyo is turning to LED light technology, a hot new area for experimentation, to squeeze three uses out of a single lamp. The company's new Eneloop Lamp is a desk light that can also work as an emergency flashlight and even send some healing energy your way--or so the company says.

clipped from techon.nikkeibp.co.jp

The "eneloop lamp" can be used as an interior lamp. The one on the left is in the "blue lamp" mode, and the other one is in the "white lamp mode." LED units that are incorporated in the core module located at the bottom of the lamp brighten the upper portion with an acrylic bar used for light guiding.

The lamp can be used as a flashlight in the "flashlight mode."

clipped from www.youtube.com

New Sanyo`s Eneloop Lamp on a test resistance in an Earthquake scenario - GreenITers.com

clipped from www.techgadgets.in

The Sanyo Eneloop lamp will be available in Japan in September for about $155 (approx Rs.7408).

Sources:

Beijing Mall with Huge LED Skyscreen

clipped from www.digitalexperience.dk

LED Skyscreen

A huge suspended LED screen forms the centerpiece of The Place in Beijing’s central business district. The screen is a massive 250 metres long and 30 metres wide, and is suspended more than 25 metres above the plaza.

clipped from www.youtube.com

clipped from www.beijingtravelbug.com

The Place Mall

This new Beijing landmark, with its striking projection screen, will house Spanish fashion chain Zara and Canadian shoe retailer Aldoâ€™s flagship store. Other outlets include Potato & Co., Folli Follie, Miss Sixty, Energie, Adidas, MAC makeup, Promod, Jessica, Chaterhouse and the Swiss Perfumery Shop. Clothing

clipped from www.meiguoxing.com

Meiguoxing.com, Your Ultimate Guide to Beijing, China

2009-02-24

Sensacell a Smart Human Interface Technology

Clipped from: +SENSACELL+

Clipped from: digitalexperience » Blog Archive » Sensacell

The Sensacell system consists of 6 inch x inch modules which comprise interactive sensor surfaces that can be assembled to any size or shape. The modules contain brightness LED lightning arrays available in many colours, shapes and sizes. This provides a wide variety of visual feedback possibilities.

Clipped from: Sensacell RGB Color Module Demo

Sensacell RGB Color Module Demo

The Sensacell system is a revolutionary human interface technology ideal for smart architecture, interactive multimedia, retail entertainment, and a host of exciting new applications. This video shows the HS61-36-RGB module in action

Clipped from: Sensacell Storefront Window Kiosk Demo

Sensacell Storefront Window Kiosk Demo

Clipped from: Sensacell Corporation Provides Interactive Floor System for the 2008 World Expo, in Zaragoza Spain.

Sensacell Corporation Provides Interactive Floor System for the 2008 World Expo, in Zaragoza Spain.

Sensacell Corporation announces its contribution to the 2008 World Expo, themed "Water and Sustainable Development." The floor graces the entrance to the Spain Pavilion, "Comunitat Valenciana." Visitors walking across the floor leave behind luminous footprints, a striking visual metaphor for the "footprint" created by the actions of mankind in his environment. The 250 Square foot (25 square meter) floor system consists of over 1000 Sensacell HSI64-36-W interactive modules, each module contains capacitive sensors and a LED lighting system, the capacitive sensors allows the floor to detect and respond to visitors footsteps right through the 20 mm thick architectural glass that forms the surface of the floor.

+SENSACELL+
digitalexperience » Blog Archive » Sensacell
Sensacell Corporation Provides Interactive Floor System for the 2008 World Expo, in Zaragoza Spain.
digitalexperience » Blog Archive » Sensacell interactive floor

2008-07-28

LumiGram Fiber Optics Fashion and Design

LumiGram a French high tech fashion and design company provides a line of fashion tops, table clothes, pillows, sculpture and more with LED illuminated fiber optics creating a colorful glow of light.