The compound is based on rare earths emitting coloured light that vary in colour with the amount of oxygen present in the sample.
it will be possible to measure oxygen using the optical microscopes already present in most hospitals. Thomas Just Sørensen is Associate professor at the Department of chemistry, Nanoscience Centre, University of Copenhagen.
which emit more light as the amount of oxygen diminishes. These, however, were incapable of measuring the amount of oxygen in cells,
whether a large amount of light signal was caused by a low oxygen concentration or a large concentration of oxygen sensitive molecules.
"You simply deduct the amount of red light from the amount of green to get a precise reading of the oxygen level.
Lucky for me that optical microscopes are kitted usually out to convert colour values to numerical values",smiles the inventor.
and Sørensen utilizes near infrared light which is highly compatible with biological studies, because it penetrates deeply into tissue,
Sørensen is particularly proud that the light signals are visible in an ordinary optical light microscope. Even though he readily admits that the microscope used for the initial testing is normal only for a when considered as individual components."
"The detector and light source was the same as on light microscopes found at any hospital, but my colleague Tom Vosch has optimized the microscope to the point where everything is almost beyond the possible.
optic flow sensors could be used as an ultra-light backup system in the event of failure on a space mission4.
which shines pulses of light into the animal. Absorption of the light by pigmented cells produces sound waves
which travel to the surface and are detected by an ultrasound scanner. By measuring the timings of the sound waves
just as lenses focus light and resonators (like the body of a guitar) amplify sound. They reported their findings in the May 8, 2015,
and whispering galleries are found in applications ranging from sensing, spectroscopy and communications to the generation of laser frequency combs.
Due to the light-like properties of graphene electrons, they can pass through unimpededno matter how high the barrierif they hit the barrier head on.
#Controlling swarms of robots with light and a single finger (w/video)( Nanowerk News) Using a smart tablet and a red beam of light,
A person taps the tablet to control where the beam of light appears on a floor. The swarm robots then roll toward the illumination,
When the person swipes the tablet to drag the light across the floor the robots follow.
Using a smart tablet and a red beam of light, Georgia Institute of technology researchers have created a system that allows people to control a fleet of robots with the swipe of a finger.
A person taps the tablet to control where the beam of light appears on a floor. The swarm robots then roll toward the illumination,
When the person swipes the tablet to drag the light across the floor the robots follow.
"In the Georgia Tech demonstration, each robot is constantly measuring how much light is in its local"neighborhood."
so that another can steal some of its light.""The robots are working together to make sure that each one has the same amount of light in its own area,
"said Egerstedt. The tablet-based control system has one final benefit: it was designed with everyone in mind.
The waveguide and the coupler made of silicon route the two parts of a split light beam to the gaps or from the gaps.
the light beams of the waveguides initiate electromagnetic surface waves, the so-called surface plasmons. The voltage applied to the polymer modulates the surface waves.
the surface waves initially enter the output optical waveguides as modulated light beams and are superimposed then.
The result is a light beam in whose intensity (amplitude), the digital information was encoded. In the experiment, the MZM works reliably over the entire spectral range of the broadband optical fiber networks of 1500 1600 nanometers at an electric bandwidth of 70 gigahertz with data flows of up to 108 gigabit per second.
The NAVOLCHI EU project serves to use the interaction of light and electrons in metal surfaces to develop novel components for optical data transmission between chips.
#Integration of quantum dots and photonic crystals produce brighter, more efficient light Recently, quantum dots (QDS) ano-sized semiconductor particles that produce bright, sharp,
developing a new method to extract more efficient and polarized light from quantum dots (QDS) over a large-scale area.
These photonic crystals limit the direction that the QD-generated light is emitted meaning they produce polarized light,
Imperial College London and the University of Buenos aires have published the results of a study testing a silicon nanodevice in the journal Nature Communications("Non-plasmonic nanoantennas for surface enhanced spectroscopies with ultra-low
or the development of silicon computing chips that process data communicated by photons of light instead of electricity.
Common laboratory analytical techniques such as Raman and fluorescence spectroscopy determine the properties of biological molecules,
Discovery image of the planet 51 Eridani b with the Gemini Planet Imager taken in the near-infrared light on December 18 2014.
mostly as infrared light,"says Macintosh. Once the astronomers zeroed in on the star, they blocked its light
and spotted 51 Eridani b orbiting a little farther away from its parent star than Saturn does from the sun
. Even though the light from the planet is very faint nearly a million times fainter than its star subsequent observations revealed that it is roughly twice the mass of Jupiter.
#New optical chip lights up the race for quantum computer The microprocessor inside a computer is a single multipurpose chip that has revolutionised people's life,
Now, researchers from the University of Bristol in the UK and Nippon Telegraph and Telephone (NTT) in Japan, have pulled off the same feat for light in the quantum world by developing an optical chip that can process photons in an infinite number
and control quantum states of light and matter. A major barrier in testing new theories for quantum science and quantum computing is the time
The new perovskite film, with the formula Srxla1-xcro3,(x up to 0. 25), conducts electricity more effectively than the unmodified oxide and yet retains much of the transparency to visible light exhibited by the pure material.
light detectors, and several kinds of electronic devices that are by nature transparent to visible light. Of particular importance are new materials that conduct electricity by using missing electrons, otherwise known as"holes."
#New, ultrathin optical devices shape light in exotic ways Caltech engineers have created flat devices capable of manipulating light in ways that are very difficult
and cameras that can be mass-produced using the same photolithography techniques used to manufacture computer microchips."
or monochromatic light oscillates at all points in space with the same frequency but varying relative delays, or phases.
Manipulating the polarization of light is essential for the operation of advanced microscopes, cameras, and displays;
and phase of light,"says study first author Amir Arbabi, a senior researcher at Caltech."
"We can take any incoming light and shape its phase and polarization profiles arbitrarily and with very high efficiency."
a metasurface device could manipulate light in novel ways that are very hard and sometimes impossible to do using current setups.
when illuminated by a horizontally polarized beam of light, and a different image when illuminated by a vertically polarized beam."
"The two images will appear overlapped under illumination with light polarized at 45 degrees, "Faraon says.
an LSC absorbs the light on a plate embedded with highly efficient light-emitters called lumophores that then re-emit the absorbed light at longer wavelengths, a process known as the Stokes shift.
This re-emitted light is directed to a micro-solar cell for conversion to electricity. Because the plate is much larger than the micro-solar cell,
With a sufficient concentration factor, only small amounts of expensive III-V photovoltaic materials are needed to collect light from an inexpensive luminescent waveguide.
imperfect light trapping within the waveguide, and reabsorption and scattering of propagating photons. We replaced the molecular dyes in previous LSC systems with core/shell nanoparticles composed of cadmium selenide (Cdse) cores
and conceal it from detection with visible light. Although this cloak is only microscopic in size,
The surface of the skin cloak was engineered meta to reroute reflected light waves so that the object was rendered invisible to optical detection
"This is the first time a 3d object of arbitrary shape has been cloaked from visible light, "said Xiang Zhang,
is the corresponding author of a paper describing this research in Science("An ultrathin invisibility skin cloak for visible light").
"It is the scattering of light-be infrared it visible , X-ray, etc.,-from its interaction with matter that enables us to detect
For the past ten years, Zhang and his research group have been pushing the boundaries of how light interacts with metamaterials,
"Creating a carpet cloak that works in air was so difficult we had embed to it in a dielectric prism that introduced an additional phase in the reflected light,
when red light struck an arbitrarily shaped 3d sample object measuring approximately 1, 300 square microns in area that was wrapped conformally in the gold nanoantenna skin cloak,
the light reflected off the surface of the skin cloak was identical to light reflected off a flat mirror,
and the phase of the scattered light so that the object remains perfectly hidden, "says co-lead author Zi Jing Wong, also a member of Zhang's research group.
The ability to manipulate the interactions between light and metamaterials offers tantalizing future prospects for technologies such as high resolution optical microscopes and superfast optical computers.
Invisibility skin cloaks on the microscopic scale might prove valuable for hiding the detailed layout of microelectronic components or for security encryption purposes.
Though the spiral had been observed in waves of light, the team study is the first to produce the pattern with electrons.
Like all light, laser pulses feature electric fields that normally point in many directions. Polarizing a laser pulse aligns these fields along one direction,
and then essentially rotates the fields around an axis. The team first pulse of circularly polarized light rotated in one direction,
#A thermal invisibility cloak actively redirects heat Light, sound, and now, heat--just as optical invisibility cloaks can bend
and diffract light to shield an object from sight, and specially fabricated acoustic metamaterials can hide an object from sound waves,
The new material, produced by grain boundary lithography, solves that problem, he said. In addition to Ren, other researchers on the project included Chuan Fei Guo and Ching-Wu"Paul"Chu, both from UH;
The grain boundary lithography involved a bilayer lift off metallization process, which included an indium oxide mask layer and a silicon oxide sacrificial layer and offers good control over the dimensions of the mesh structure.
an element used in incandescent light bulbs. As the sample was tilted 62 times the researchers were able to slowly assemble a 3-D model of 3, 769 atoms in the tip of the tungsten sample.
The change from crystalline to amorphous (storing data) and from amorphous to crystalline (erasing data) is initiated by ultrashort light pulses.
For reading out the data, weak light pulses are used. Permanent all-optical on-chip memories might considerably increase future performance of computers
#Pushing the limits of lensless imaging Using ultrafast beams of extreme ultraviolet light streaming at a 100,000 times a second, researchers from the Friedrich Schiller University Jena,
Not only did they make the highest resolution images ever achieved with this method at a given wavelength,
The researchers'wanted to improve on a lensless imaging technique called coherent diffraction imaging, which has been around since the 1980s.
creating a diffraction pattern. By analyzing that pattern, a computer then reconstructs the path those photons must have taken,
With more photons, at a wavelength of 33 nanometers, the researchers were able to make an image with a resolution of 26 nanometers--almost the theoretical limit."
"Nobody has achieved such a high resolution with respect to the wavelength in the extreme ultraviolet before, "Zürch said.
The ultrafast laser also overcame another drawback of conventional table-top light sources: long exposure times.
Thanks to the new high-speed light source, Zürch and his colleagues have reduced the exposure time to only about a second--fast enough for real-time imaging.
#Pioneering research develops new way to capture light-for the computers of tomorrow The key breakthrough will allow large quantities of data to be stored directly on an integrated optical chip,
data transfer by means of light have long since become part of our everyday life, data on a computer are processed still
The team of scientists from Germany and England have made a key breakthrough by capturing light on an integrated chip,
narrow operational bandwidth and time consuming manufacturing processes. ur lens concept has a 3d subwavelength capability that is 30 times more efficient, able to tightly focus broadband light
nanometer particles with the ability to absorb light and re-emit it with well-defined colors.
"For example, the elapsed time between light absorption and emission can be extended to be more than 100 times longer compared to conventional quantum dots,
"this tool should provide fast and reliable characterization of the different mechanisms cellular proteins use to bind to DNA strands information that could shed new light on the atomic-scale interactions within our cells
They also looked at an indirect and much less studied effect of UV LIGHT. When the active ingredients of sunscreen absorb UV LIGHT a chemical change triggers the generation of oxygen-carrying molecules known as reactive oxygen species (ROS.
If a sunscreen agents penetrate the skin, this chemical change could cause cellular damage, and potentially facilitate skin cancer. ommercial chemical sunblock is protective against the direct hazards of ultraviolet damage of DNA,
"In this light, Lu's invention represents a major advancement for the mobile health industry.""After producing the cut-and-pasted patches,
#Brightness-equalized quantum dots improve biological imaging Researchers at the University of Illinois at Urbana-Champaign have introduced a new class of light-emitting quantum dots (QDS) with tunable and equalized fluorescence brightness
"In this work, we have made two major advances--the ability to precisely control the brightness of light-emitting particles called quantum dots,
because the amount of light emitted from a single dye is unstable and often unpredictable.
These attributes obscure correlations between measured light intensity and concentrations of molecules,"stated Sung Jun Lim, a postdoctoral fellow and first author of the paper"
and improve color tuning in light-emitting devices. In addition, BE-QDS maintain their equal brightness over time
They demonstrated a first direct observation of the so-called vacuum fluctuations by using short light pulses while employing highly precise optical measurement techniques.
The duration of their light pulses was ensured to be shorter than half a cycle of light in the spectral range investigated.
when the intensity of light and radio waves completely disappears. These findings are of fundamental importance for the development of quantum physics
representing the quantum ground state of light and radio waves. However, until now direct experimental proof of this basic phenomenon has been considered impossible.
From spontaneous emission of light by excited atoms e g. in a fluorescent tube to influences on the structure of the universe during the Big Bang:
It's difficult to localize visible light below its diffraction limit, about 200-300 nanometers, and as components in electronic semiconductors have shrunk to the nanometer scale,
Now researchers at the University of Rochester have demonstrated a key achievement in shrinking photonic devices below the diffraction limit--a necessary step on the road to making photonic circuits competitive with today's technology.
The scientists developed a nanoscale photodetector that uses the common material molybdenum disulfide to detect optical plasmons--travelling oscillations of electrons below the diffraction limit
--and successfully demonstrated that light can drive a current using a silver nanowire.""Our devices are a step towards miniaturization below the diffraction limit,
"said Kenneth Goodfellow, a graduate student in the laboratory of the Quantum Optoelectronics and Optical Metrology Group, The Institute of Optics, University of Rochester, New york."
"It is a step towards using light to drive, or, at least complement electronic circuitry for faster information transfer."
The device expands on previous work demonstrating that light could be transmitted along a silver nanowire as a plasmon
the light corresponded to the band gap of Mos2, rather than solely to the laser's wavelength, demonstrating that the plasmons effectively nudged the electrons in Mos2 into a different energy state."
"The natural next idea would be to see if this type of device would be able to be used as a photodetector,
and deposited metal contacts onto that same end with electron beam lithography. They then connected the device to equipment to control its bias,
finding that it was sensitive to the polarization of the incoming light and was at its strongest
when the light was polarized parallel to the wire. They also found that the device was sensitive to the laser's excitation wavelength,
and performance was limited at shorter wavelengths due to ineffective plasmon propagation and at longer wavelengths due to the band gap of molybdenum disulfide."
"Full photonic circuits are some time in the future, but this work helps to feed the current effort,
using heat, instead of light, to measure magnetic systems at short length and time scales. Researchers led by Greg Fuchs,
The technique relies on analysis of reflected light from short laser pulses to gain information about magnetization. Unfortunately
the physics of optical diffraction limit how small a laser spot can be used, which ultimately limits the resolution of the technique.
The researchers at IBS used a multi-technique approach, combining solid-state NMR spectroscopy, simulations of molecular dynamics and X-ray crystallography.
The light-generating DNA antibody detecting nanomachine is illustrated here in action, bound to an antibody.
which generates a light signal. The sensor does need not to be activated chemically and is rapid-acting within five minutes-enabling the targeted antibodies to be detected easily, even in complex clinical samples such as blood serum."
Microscopy and scattering data gathered at the Molecular Foundry and the Advanced Light source also a DOE Office of Science user facility located at Berkeley Lab,
and regulate the exchange of light, heat, and moisture. They thus play a special role in nature and technology.
In the journal Nature Nanotechnology("Surface imaging beyond the diffraction limit with optically trapped spheres"),the Freiburg physicist Prof.
scattered light and thermal noise. The tiny plastic sphere, the probe, appears to move in a chaotic manner inside the light trap due to the so-called thermal noise.
"Once there, the probe records the scattered light from the surface and subtracts it. But before the probe can escape,
"Just as conventional lenses can be used to focus a light beam, our configuration can be used to focus an electron beam.
a technique using electrons (instead of light or the eyes) to see the characteristics of a sample,
then convert that light into an electrical charge proportional to its intensity and wavelength. In the case of our eyes, the electrical impulses transmit the image to the brain.
"In this structure--unlike other photodetectors--light absorption in an ultrathin silicon layer can be much more efficient
and improve light absorption without the need for an external amplifier.""There's a built-in capability to sense weak light,
"Ma says. Ultimately, the new phototransistors open the door of possibility, he says.""This demonstration shows great potential in high-performance and flexible photodetection systems,"says Ma,
when exposed to ultraviolet light. The way tiny vessels are reconnected now includes stitches applied in microsurgery.
dissolving quickly under ultraviolet light to allow restored circulation. Smith placed the amino acid into the sequence in a way that allows precise control
when a plant uses light to break down water and carbohydrates, which are the main energy sources for the plant.
Light with photo energy can penetrate indirect band gap materials much more easily without getting absorbed
chief scientist and project leader at Honda Research Institute USA Inc."Our approach combines novel nanomaterials with continuous ultraviolet light radiation in the sensor design that have been developed in our laboratory by lead researcher Dr
the zone plates focus by diffraction--bending light as it passes the edge of a barrier.
"Essentially, it has to absorb the light completely. It's hard to find a material that doesn't reflect
Incoming light bouncing between individual silicon nanowires cannot escape the complex structure, making the material darker than dark.
Each individual lens resembles a bull-eye of alternating light and dark. Arrays of lenses formed within a flexible polymer bend
the zone plates focus by diffraction--bending light as it passes the edge of a barrier.
"Essentially, it has to absorb the light completely. It's hard to find a material that doesn't reflect
Incoming light bouncing between individual silicon nanowires cannot escape the complex structure, making the material darker than dark.
"I believe that this work will benefit researchers in the area of surface plasmonics by providing a new strategy/design for enhancing the surface enhanced Raman spectroscopy (SERS) detection limit,
which we might have to reexamine in light of new evidence. His team is now aiming to use cryofixation on other parts of the brain and even other types of tissue
But the fibrils that are believed to be most harmful are too tiny to be seen using an optical microscope.
so that light can now go through. This disturbance on the membrane the imprint of the protein fibers is transmitted down through the liquid crystal film,
so that it is large enough to be seen in polarized light with a simple optical microscope. Microscopic bright spots Seen through the microscope,
bright where the liquid crystal has been disturbed to let light pass. he liquid crystal is actually reporting what happening to the aggregates at the interface,
which detect strain by measuring shifts in the wavelength of light reflected by the optical fiber.
allowing light to escape. By measuring the loss of light, the researchers are able to calculate strain or other deformations.
Park said this type of flexible optical sensor could be incorporated into soft skins. Such a skin would
#A Natural light Switch: Identifying and Mapping Protein Behind Light Sensing Mechanism MIT scientists, working with colleagues in Spain, have discovered
benefit from knowing whether they are in light or darkness. The photoreceptors bind to the DNA in the dark,
such as the engineering of light-directed control of DNA transcription, or the development of controlled interactions between proteins. would be interested very in thinking about
from the International Centre for Radio astronomy Research, said scientists came to this conclusion after conducting the largest multi wavelength survey ever put together. e used as many space
and ground-based telescopes we could get our hands on to measure the energy output of over 200,000 galaxies across as broad a wavelength range as possible,
In total the team measured outputs across 21 different wavelengths from ultraviolet (characterises younger stars) to the far infrared (characterises younger stars.
but this work shows that it happening across all wavelengths p
#NASA Mars isolation experiment begins SIX people are about to shut themselves inside a dome in Hawaii for a year,
involves measuring the way light is scattered off large molecules and structures inside cells. Cancer cells can be detected
which harness the unusual properties of light-bending metamaterials, have shown theoretical promise for years. But outside of dramatic illusions made with lenses,
To redirect the short wavelengths of visible light requires tiny structures so instead early designs deflected longer wavelengths like microwaves.
Cloaks have struggled also to handle many wavelengths of light at once. Now, a team at Zhejiang University in Hangzhou, China, has taken a significant step forward by making a cloak for infrared radiation,
whose wavelengths are only just too long to see. All animals including humans emit infrared as heat.
Snakes can sense this radiation even in darkness, using it to hunt down their prey. e want to simulate the scene of catching a mouse,
#Migraines triggered by protein deep in the brain It can start with flashing lights, a tingling sensation and a feeling of unease, followed by excruciating pain.
#Echoless light could help send signals through walls and skin IT a call with no response.
and shone light through it. As expected, the light emerging at the other end had become distorted.
They measured the exact degree of distortion and how the profile of the pulse changed on its journey through the fibre.
Finally, they created a light pulse with the exact cross-section needed to counteract the distortion and emerge from the fibre intact and found that it did just that. ven
holograms and beyond Novel tech that manipulates light has applications beyond holograms, from studying alien worlds to making cellphones more energy efficient In 2010,
and make novel hologram technologies. He created a tool that did much more. The technology is a new way to manipulate light,
with applications from studying alien worlds to making cellphones more energy efficient.""Not long after we received the NSF funding,
which allows us to create nearly perfect geometric phase holograms, "says Escuti, an engineer at North carolina State university."
"To make geometric phase holograms, the DWLS"prints"using an ultraviolet laser on a super-thin film--only about 50 nanometers thick.
The film is made of a photoreactive polymer that responds to both the intensity and the polarization of the light.
you have to understand that it doesn't have an inkjet--it prints light, and it prints in four dimensions.
And it can also vary the intensity of the light. But, crucially, it is also capable of controlling the orientation angle of the linear polarization of the light.
Think of a beam of light as a wiggling wave, which vibrates in a perpendicular direction relative to the direction it is traveling.
Control of the orientation angle of the linear polarization of light means control of the direction that the wave is wiggling.
And this polarization angle can be manipulated without changing the angle the light is traveling. In other words, a laser can be pointed directly at an object and
One reason the DWLS is unique is that it produces geometric phase holograms that are smoothly varying
This prevents light from"leaking"out of the pattern and corrupting the signal coming out of the hologram.
From the lab to the stars After creating the DWLS, Escuti looked for potential applications.
in theory, can use light to help them unravel the mysteries of the universe. But these theoretical designs were hampered often by the limits of technology."
and instrument designs that could make better use of the light collected by telescopes, "Escuti says."
if we could make holograms with specific characteristics that had previously been technologically impossible. And we could."
his team has provided the astronomers with geometric phase holograms that they have used build advanced coronagraphs--telescopes that can see things close to stars--to study exoplanets beyond our solar system."
"They wanted to redistribute the blazing light of the halo around a star, so that the faint light coming from a planet orbiting that star can be observed with better contrast
--and then analyze the planet's light to learn about its composition and other characteristics,
"With these components and techniques, we have for the first time in perhaps many decades fundamentally expanded the astronomer's toolkit for manipulating light from astronomical sources,
Down to earth applications In addition to astronomy, the DWLS has found use in creating geometric phase holograms for use in mobile displays, holographic imaging,
and designed in partnership with Snik for the International Year of Light. Escuti is continuing to work on new applications with direct support from the National Science Foundation and the Jet propulsion laboratory
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