Shining a light on the cells triggers a cascade of biochemical reactions that transfer electrons along a chain of molecules#and switches the transistor on.
or using wavelengths of light that are absorbed easily by chlorophyll, increases the rate of photosynthesis and produces a larger current through the transistor.
A microscope sends sheets of light rather than a conventional beam through the fish's brain,
for the latest study, they modified light detectors and other aspects of the system to increase the rate of imaging tenfold.
The new knowledge the project has generated can shed more light on diseases that affect the myelin
However, this approach has a fundamental limit known as the diffraction limit, which means that it can be used to visualize objects much smaller than the wavelength of the light being used.
For example if you are using blue-green light with a wavelength of 500 nanometers, you can see anything smaller than 250 nanometers. nfortunately,
in biology that right where things get interesting, says Boyden, who is a member of MIT Media Lab and Mcgovern Institute for Brain Research.
contrary to most other methods that beat the diffraction limit for microscopy, which can be 1,
#Printing Color Images Without Ink A new technology creates colorful images by manipulating light rather than applying ink.
and corresponded to the desired absorption of light at various wavelengths. When light was shined onto the structure
the holes allowed certain wavelengths through at specific locations, producing the colorful logo. nlike the printing process of an inkjet or laserjet printer,
where mixed color pigments are used, there is no color ink used in our structural printing process only different hole sizes on a thing metallic layer, Dr. Jie Gao,
#Floating, Touchable'Fairy Lights'Unveiled A team of researchers from Japan has found a way to use a high-speed laser to create a touchable plasma display in mid-air.
Unlike many laser lights, these don produce a burning sensation when touched. By upping the speed of the laser from a nanosecond to a femtosecond
--which is one millionth of one billionth of one second--the researchers have increased the level of safety
These lasers do, however, generate haptic sensations, or hock wavesthat feel like an mpulse on the finger
as if the light has physical substance, the researchers say. DNEWS: Laser Technique Etches Water Repellence Into Metalthe team of researchers from the University of Tsukuba, Utsunomiya University,
Nagoya Institute of technology and the University of Tokyo believe their laser-induced plasma, which they've dubbed"Fairy Lights,
"has advantages over other 3-D displays. For starters, it doesn require physical matter arranged
and suspended in air to emit light, and it doesn require wires and structures that obstruct the line-of-sight.
Laser-induced plasma can also be controlled precisely. The researchers behind the project believe the technology has several applications,
Laser Levitates Diamondsalthough the displays right now are tiny, at just eight cubic millimeters, there hope that they will become larger as the technology progresses.
e developed a modulation algorithm that increases the throughput of data in visible light communications, Maite Brandt-Pearce,
which stands for Visible light Network Communications. They are now working on a prototype for potential investors:
when the light is on. Bring The nternet Of Thingsinto Your Homeesearchers have called it i-Fi?
the concept could provide a big boost to connectivity speeds with the potential to use every light in a building as an Internet transmitter. via Phys. or a
#'Dog Nose'Light Sniffs Out Disease Here a riddle: What kind of light can smell? Answer:
An optical dog nose. Researcher James Anstie at the University of Adelaide and his team are developing an instrument theye dubbed an optical dog nose that uses a specialized laser known as an optical frequency comb to provide a quick and noninvasive way to analyze a person
breath for disease. Gold nanoparticles Could Detect Disease: Discovery Newsprevious studies have shown that diseases such as lung and esophageal cancer,
Using light to smell might be a little counterintuitive, but stick with us for a moment. Anstie and his team shine the laser onto a sample of gas.
Since each molecule in the universe absorbs light at different optical frequencies, an odor has its own unique signature. ather than sniffing out a variety of smells as a dog would,
the laser system uses light to ensethe range of molecules that are present in the sample,
As for future plans, Anstie of the University of Adelaide Institute for Photonics and Advanced Sensing expects to have a working prototype of the device within three years and a market-ready product within five years.
which the driver is going, the coupe lights up accordingly. When hit with an electric charge, this special RF-C glows because of an electroluminescent paint.
the quicker the lights will glow. Although Lexus doesn't plan to add this feature to any current cars,
Using near-IR spectroscopy, the SCIO (pronounced ki-oh uses a source light and an optical sensor to identify the molecular structure of any given material.
Different types of molecules vibrate in unique ways and those vibrations interact with the light to create an optical signature.
By analyzing the light spectrum of each specific signature, the SCIO can tell what molecules are present in a material or substance.
the S3 center emits a glow when struck by a pulse of laser light. Scientists can then use the lifetime of the resulting luminescence to calculate the temperature of the probe:
This produces luminescence at two separate wavelengths that have lifetimes ranging from 277 millionths of a second to about 100 billionths of a second.
since the visible light emitted by the diamond probes faint green glowoes not penetrate whole human tissue very well. nly infrared light can penetrate into your body.
You cannot do that by using visible light, Jaque says. Still, a micron-scale look at the thermodynamics of human cells with picosecond time resolution would be a tremendous tool for scientists.
By positioning mirrors along the channel that reflect light into a microscope the researchers could observe the levitating cells in real time.
#Scientists arm cells with tiny lasers In a feat of miniaturization that makes your Apple Watch look lame,
scientists have implanted tiny lasers within living cells. The lasers can be used to track individual cells for days and weeks,
the researchers report this week in Nano Letters. A laser requires two things: a material that can be stimulated in some way to produce light
and a"resonant cavity"that will ring with light waves of particular wavelengths much as an organ pipe will ring with sound waves of distinct frequencies.
Light resonating in the cavity stimulates the material to emit even more light, greatly amplifying the light to create a laser.
Researchers had used previously living cells to fashion lasers by loading the cells with fluorescent proteins
and placing them within a resonant cavity. Now, a team of physicists and biologists have gone a key step further,
coaxing a cell to envelop a tiny plastic sphere that acts like a resonant cavityhown in green in the micrograph abovehus placing a whole laser within a cell.
The spheres are seasoned with a fluorescent dye, so that a zap with one color of light makes them radiate at another color.
The light then resonates in the sphere, triggering laser action and amplifying itself. Crucially, each laser shines at a couple of distinctive wavelengths depending on the precise size of the sphere,
as shown in the graph. So although demonstrated only in cultured cells, the technique might someday be used to track the movement of individual cells,
say, within cancerous tumors u
#Eye drops could dissolve cataracts Cataracts cloud the eyes of tens of millions of people around the world and nearly 17.2%of Americans over the age of 40.
Currently, the only treatment is surgeryasers or scalpels cut away the molecular grout that builds in the eye as cataracts develop,
and surgeons sometimes replace the lens. But now, a team of scientists and ophthalmologists has tested a solution in dogs that may be able to dissolve the cataract right out of the eye lens.
#Desktop sonic black hole emits Hawking radiation A model black hole that traps sound instead of light has been caught emitting quantum particles thought to be the analogue of the theoretical Hawking radiation.
Their gravity is so strong that nothing not even light can escape from their edge a boundary called the event horizon.
of which trapped photons using laser pulses in a fibre optic-cable cable. The team claimed this had produced Hawking radiation
The team used one laser to confine the BEC to a narrow tube and another to accelerate some of it faster than the speed of sound.
and forth between the inner and outer horizons triggering the creation of more Hawking phonons each time much like a laser amplifies light.
Physicists call this effect a black hole laser The Hawking radiation exponentially grows it self-amplifies Steinhauer says.
The device looks like a funky golf club with a laser at the end says PG&E spokesperson Hailey Wilson.
A galaxy should emit about 10 per cent of its light in the mid-infrared range says team leader Jason Wright at Pennsylvania State university.
We have found several dozen galaxies giving out a superlative amount of mid-infrared light says Wright.
#Largest laser gives diamond a record-setting squeeze Diamond has been subjected to the wrath of the world's largest laser
Using the National Ignition Facility (NIF) at Livermore Smith's team bombarded tiny targets with 176 laser beams to put the squeeze on diamond.
and then precisely timed laser pulses to strike the cylinder's interior walls. This caused the gold to emit an avalanche of X-rays that bombarded the stone triggering powerful compression waves inside it.
Microlensing detects planets by watching how their gravity affects the light of a distant background star.
As one star passes in front of another as seen from Earth light from the background star is bent gravitationally
The planet isn't blocking the background star's light. It's just that the mathematics of focusing is disrupted by the planet's gravity he says.
and coloured lights Spacex CEO Elon musk gave the world its first glimpse of the upgraded Dragon spacecraft.
whether and by how much the light from the supernova is being messed with by other things like nearby galaxies or the expansion of the universe.
For example the gravity from a massive object like a galaxy can magnify light from another object like a supernova bending its light waves
its light is being lensed by a galaxy in front of it. The supernova PS1-10afx was discovered in 2010 using the Pan starrs telescope in Hawaii.
Since we know what the light from PS1-10afx should look like without gravitational lensing a standard candle any differences can be attributed to the mass of the galactic lens
#Star dust casts doubt on recent big bang wave result An imprint left on ancient cosmic light that was attributed to ripples in spacetime
Unlike BICEP2 Planck observes at a range of different wavelengths. Because emissions from dust vary with wavelength this should allow researchers to better separate out the contributions to polarised light from dust.
For sure this BICEP2 result will put even more pressure on Planck's next release says Fabio Finelli a Planck team leader at Italy's National Institute for Astrophysics in Bologna.
Gas in Earth's upper atmosphere is ionised by ultraviolet light from the sun and the resulting plasma becomes trapped by magnetic fields in a doughnut-shaped ring around the planet.
Laser signals carry more data but the light is almost undetectable by the time it reaches Earth. Now a nanoscale light detector could make such deep-space missives easier to read.
So says Richard Mirin at the US National Institute of Standards and Technology (NIST) in Boulder Colorado who developed the detector with NASA.
The most reliable way of doing this is to vary the time interval between light pulses with a long interval representing a 0 say
Laser communication is one of the technologies we are considering says Bas Lansdorp CEO of the Mars One project which aims to place a human colony on Mars by 2025.
This development by NIST makes long-distance laser communication even more interesting g
#Japan's huge magnetic net will trawl for space junk SOMEWHERE in Earth's orbit a satellite explodes into a terrifying cloud of debris. Moments later Sandra bullock
The net is fitted with sensors that look for light reflecting from small pieces of debris and automatically aligns itself
#NASA orbiter will use laser to bring broadband to moon The man in the moon is about to get his own version of a broadband connection as well as a visit from China.
NASA's LADEE moon orbiter due to launch on 7 september will use laser pulses to exchange high-capacity signals with Earth.
or shine but their relatively long wavelengths limit the information they can transmit in a given time period.
So LADEE will carry a laser with a near-infrared wavelength that is thousands of times shorter as part of the Lunar Laser communication Demonstration experiment.
But using shorter wavelengths for communication presents new challenges. Laser beams do not spread out as much as radio waves
while they travel which means that they must be aimed very precisely at detectors on the ground.
Earth's atmosphere including clouds can also thwart laser signals. To maximise the chance of cloudless skies LLCD will be able to beam its light to any of three detectors in New mexico California or Spain.
For this mission there is a better than 90 per cent chance of any one of those sites being open Cornwell says.
or so of LADEE's planned four months in lunar orbit but a follow-on mission called LCRD will test laser links from Earth orbit for two years beginning in 2017.
It will deploy Sprint-A into low Earth orbit where the spacecraft will take aim at the planets using cameras and sensors that record extreme-ultraviolet light.
Extreme UV is a range of light suitable for observing planetary atmospheres says Shujiro Sawai of the Japan aerospace exploration agency (JAXA.
When a planet transits a star the amount of light it blocks is used to calculate its size.
because it requires teasing out subtle periodic variations in a star's light. Fabienne Bastien of Vanderbilt University in Tennessee and colleagues used Kepler data to watch instead for flickers in starlight due to short-lived convection cells or granules on the star's surface.
Choreographed high-power lasers or electron beams can fuse and sculpt metal powders into high-performance machine parts.
Instead Gianluca Sarri at Queen's university Belfast UK and colleagues used rapid laser bursts to make positrons in their smaller budget device.
The laser pulse ionises inert helium gas generating a stream of high-speed electrons. This electron beam is directed at a thin metallic foil
In 2008 scientists at the Lawrence Livermore National Laboratory in California produced large quantities of antimatter by directing an extremely powerful laser at a tiny gold disc.
They needed much stronger lasers and those lasers are expensive. Also they produced streams of positrons that were extremely broad
whereas our jet is a hundred times narrower and remains pencil-like as it propagates he adds.
and the tabletop method makes searing-hot beams of particles moving at near light speed. As an alternative says Sarri the beams can be used to mimic the way particle fountains from black holes
and colleagues observed the star at three wavelengths: one sensitive to dust grains a millimetre across
So Cahoy and colleagues are working on using light to transfer data instead. Easier to focus
laser signals could make it possible to build smaller, lower powered satellites that can still talk to the ground easily."
then come together in space to form a light, powerful satellite. A network of such orbiters should be able to provide coverage that is similar to the signals terrestrial cellular towers already pump out."
and using a blue backlight to energize them, QD Vision has developed an optical component that can boost the color gamut for LCD televisions by roughly 50 percent,
pixels are illuminated by a white LED backlight that passes through blue, red, and green filters to produce the colors on the screen.
But this actually requires phosphors to convert a blue light to white; because of this process, much light is lost,
and displays only reach about 70 to 80 percent of the National Television Standard Committee color gamut.
Manufacturers use a blue LED in the backlight, but without the need for conversion phosphors.
As blue light passes through the Color IQ tube, some light shines through as pure blue light
With more light shining through the pixels, LCD TVS equipped with Color IQ produce 100 percent of the color gamut,
However this DNA is produced only when activated by the presence of a predetermined molecule or another type of input such as light.
the researchers developed a prototype device by using a laser to cut a hole in a silicone tube to add drugs. ight
which can be identified with great precision by the wavelength of their fluorescent emissions. The new method produces the combination of desired properties in as small a package as possible Bawendi says which could help pave the way for particles with other useful properties such as the ability to bind with a specific type of bioreceptor or another
The emitters like most nanoscale silicon devices were produced through photolithography a process in which patterns are transferred optically to layers of materials deposited on silicon wafers;
Nanoprintingvelsquez-Garca believes that using arrays of emitters to produce nanodevices could have several advantages over photolithography the technique that produces the arrays themselves.
It should absorb virtually all wavelengths of light that reach Earth s surface from the sun but not much of the rest of the spectrum since that would increase the energy that is reradiated by the material
The material is a two-dimensional metallic dielectric photonic crystal and has the additional benefits of absorbing sunlight from a wide range of angles
Most of the sun s energy reaches us within a specific band of wavelengths Chou explains ranging from the ultraviolet through visible light and into the near-infrared.
The material is made from a collection of nanocavities and you can tune the absorption just by changing the size of the nanocavities Chou says.
Another key characteristic of the new material Chou says is that it is matched well to existing manufacturing technology.
or when its distance is a specific multiple of the wavelength of sound. Maintaining that precise distance is a tall order
Companies sell medications with barcodes others sell software or barcode scanners. Hospitals have to make all these things work together
Furthermore the researchers found that they could reverse the emotional association of specific memories by manipulating brain cells with optogenetics a technique that uses light to control neuron activity.
Then for mice that had received the fear conditioning the researchers stimulated the labeled cells in the dentate gyrus with light
For male mice that had received originally the fear conditioning they activated the memory cells involved in the fear memory with light for 12 minutes while the mice spent time with female mice.
and had avoided the side of the chamber where their hippocampal cells were activated by the laser now began to spend more time in that side
a robot made almost entirely from parts produced by a laser cutter that folds itself up
which would self-assemble from laser-cut materials when uniformly heated. The new work is similar
The robot is built from five layers of materials all cut according to digital specifications by a laser cutter.
After the laser-cut materials are layered together a microprocessor and one or more small motors are attached to the top surface.
but also light much as window blinds tilt to filter the sun. Researchers say the work could lead to waterproofing and anti-glare applications such as smart windows for buildings and cars.
Zhu shone a laser through the material while tilting the pillars at various angles and found she could control how much light passed through based on the angle at which the pillars bent.
In principle she says more complex magnetic fields could be designed to create intricate tilting patterns throughout an array.
But at the boundary itself, the camera sensor receives both red and blue light, so it averages them out to produce purple.
The sensor of a digital camera consists of an array of photodetectors millions of them, even in commodity devices.
so that it reads off the measurements of one row of photodetectors at a time. Ordinarily, that not a problem
#Light pulses control graphene s electrical behavior Graphene, an ultrathin form of carbon with exceptional electrical optical and mechanical properties, has become a focus of research on a variety of potential uses.
Now researchers at MIT have found a way to control how the material conducts electricity by using extremely short light pulses
which could enable its use as a broadband light detector. The new findings are published in the journal Physical Review Letters in a paper by graduate student Alex Frenzel Nuh Gedik and three others.
The researchers found that by controlling the concentration of electrons in a graphene sheet they could change the way the material responds to a short but intense light pulse.
The researchers then illuminated graphene with a strong light pulse and measured the change of electrical conduction by assessing the transmission of a second low-frequency light pulse.
In this case the laser performs dual functions. We use two different light pulses: one to modify the material and one to measure the electrical conduction.
Gedik says that the pulses used to measure the conduction are much lower frequency than the pulses used to modify the material behavior.
to allow laser pulses to pass through it. This all-optical method avoids the need for adding extra electrical contacts to the graphene.
Additionally the short light pulses allow the researchers to change and reveal graphene's electrical response in only a trillionth of a second.
which causes the conductivity to decrease when the electron temperature increases under the illumination of the laser pulse.
The researchers say the work could aid the development of new light detectors with ultrafast response times and high sensitivity across a wide range of light frequencies from the infrared to ultraviolet.
While the material is sensitive to a broad range of frequencies the actual percentage of light absorbed is small.
The angle at which light should seem to arrive from the simulated image is sharper than the angle at
which light would arrive from the same image displayed on the screen. So the physical pixels projecting light to the right side of the pupil have to be offset to the left
That requires that a transparency patterned with an array of pinholes be laid over the screen blocking more than half the light it emits.
while letting much more light pass through. Wetzstein envisions that commercial versions of a vision-correcting screen would use the same technique.
In image-processing schemes with incoherent light normal light that we have around us nonlaser light you're always dealing with intensities.
#Making the cut Diode lasers used in laser pointers barcode scanners DVD players and other low-power applications are perhaps the most efficient compact and low-cost lasers available.
Attempts have been made over the years to amplify the brightness of these valuable lasers for industrial applications such as welding and cutting metal.
But boosting power usually means decreasing beam quality or focus. And the beam never gets intense enough to melt metal.
Now MIT Lincoln Laboratory spinout Teradiode is commercializing a multikilowatt diode laser system that s bright enough to cut
and weld even through a half-inch of steel at greater efficiencies than today s industrial lasers.
The 4-kilowatt Terablade runs on a novel power-scaling technique developed at MIT that manipulates individual diode laser beams into a single output ray.
This allows for boosting power of a diode laser while preserving a very focused beam. The Terablade has comparable beam quality as compared with traditional manufacturing lasers such as carbon dioxide disk
and fiber says Teradiode cofounder and vice president Robin Huang a former Lincoln Laboratory researcher and Terablade co-inventor.
However because the Terablade is a direct-diode laser it has the highest efficiency and lowest cost of ownership as compared with these other lasers.
Huang says Terablade represents a third generation of industrial lasers. The first generation which evolved a few decades ago was carbon dioxide lasers in
which electricity runs through a gas to produce light. These are very bright but can be as large as trucks
and operate at about 20 percent efficiency. Then came diode-pumped solid-state (DPSS) lasers including disk
and fiber that first transfer energy from diode lasers into a medium usually a crystal before converting it into a laser beam.
These operate only up to about 30 percent efficiency. But the Terablade aptly called a direct-diode laser uses light directly from the diodes skipping the DPSS conversion step
and saving energy Huang says. This means the Terablade operates with just as much power and brightness as all other industrial lasers about 2600 megawatts per square centimeter per steradian at roughly 40 percent efficiency.
At the core of the Terablade is a power-scaling technique known as wavelength beam combining (WBC
or incoherent beam combining developed by Huang and former Lincoln Laboratory researcher and Teradiode cofounder Bien Chann who is now the company s vice president and chief technology officer.
Diode lasers are tiny semiconductor devices that when electrically charged cause electrons to create photons of the same wavelength
or color traveling in the same direction. When fed through an output collimation lens this creates a ray of laser light.
An individual diode laser in say a laser pointer can emit a beam in infrared and near-infrared wavelengths that can be focused tightly to a very small spot
but with little power Huang explains. Overlapping many similar beams at differing wavelengths however produces a beam that focuses on a small spot making it very intense.
And the number of overlapping beams with differing wavelengths can be very high. In the early 2000s Huang Chann and Lincoln Laboratory colleagues built a few prototype lasers based on WBC technology.
One which reached a power level of 50 watts was a world s record for diode laser brightness at that time Huang says.
In 2009 Huang and Chann along with Fred Leonberger a former Lincoln Laboratory staffer who now serves on Teradiode s board of directors
and former CEO David Sossen launched Teradiode now in Wilmington Mass. to bring the technology to market.
The company s current CEO is photonics entrepreneur Parviz Tayebati. Today the WBC-based Terablade is a laser module that contains diode laser bars (long arrays of diode lasers) a transform lens a diffraction grating and an output lens.
The light from the diode lasers passes through a transform lens onto the carefully positioned diffraction grating a plate of glass scratched with parallel lines.
However instead of dispersing light at different angles which it s designed to do the grating forces the beams into the same direction superimposing them on one another.
There are a few other multikilowatt direct-diode lasers but they run on another popular and similar power-scaling technique called side-by-side
or spatial beam combining that joins together the beams of similar wavelengths. As the number of diode lasers increases the beam quality degrades resulting in a large focused spot limiting the beam s intensity.
This means the Terablade outputs a beam roughly 100 times brighter than these scaled-up direct-diode laser models Huang says.
Each Terablade module outputs about 1000 watts and can be scaled to increase power. The company has developed also a commercial Terablade system:
a 3-foot cube that comes with multiple laser engines a control computer power supplies and an output head for welding
and cutting among other components. Increasingly the Teradiode technology is finding customers in countries such as Japan
and Germany where energy costs are high Huang says. In April the company began shipping its system to Panasonic Welding Systems in Europe and Japan.
Other customers include top global builders of industrial laser-based machines and system integrators. More broadly our vision is to revolutionize the laser industry Huang says by introducing powerful direct-diode lasers to various applications across the globe.
In the future he adds the company is also looking toward defense applications. One idea is to build a laser that acts as a heat-seeking missile deterrent:
It fires infrared laser light at the missile which would confuse the missile s programming and cause it to lose its target.
The laser s compact design would allow it to be mounted on a fighter jet. With the Terablade technology Huang says The sky is the limit literally y
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