Lasers Generate Underwater Sound

Scientists at the Naval Research Laboratory are developing a new technology for use in underwater acoustics. The new technology uses flashes of laser light to remotely create underwater sound. The new acoustic source has the potential to expand and improve both Naval and commercial underwater acoustic applications, including undersea communications, navigation, and acoustic imaging. Dr. Ted Jones, a physicist in the Plasma Physics Division, is leading a team of researchers from the Plasma Physics, Acoustics, and Marine Geosciences Divisions in developing this acoustic source.

Efficient conversion of light into sound can be achieved by concentrating the light sufficiently to ionize a small amount of water, which then absorbs laser energy and superheats. The result is a small explosion of steam, which can generate a 220 decibel pulse of sound. Optical properties of water can be manipulated with very intense laser light to act like a focusing lens, allowing nonlinear self-focusing (NSF) to take place. In addition, the slightly different colors of the laser, which travel at different speeds in water due to group velocity dispersion (GVD), can be arranged so that the pulse also compresses in time as it travels through water, further concentrating the light. By using a combination of GVD and NSF, controlled underwater compression of optical pulses can be attained.

via NRL Press Release.

The Recent Future / September 7, 2009 / Tech / 0 Comments

Japan Plans $21 Billion Solar Space Post to Power 294,000 Homes

The concept of space-based solar power was introduced way back in 1968, but it’s only recently that the world has latched on to the idea. Japan is definitely getting in on the action with its latest spacey plan – a $21 billion solar-powered generator in the heavens to produce one gigawatt of energy, or enough to power 294,000 homes. The Japanese government announced the plan back in June, but there has been an important new development – Mitsubishi Electric Corp. and industrial design company IHI Corp. are now teaming up in the race to develop new technology within four years that can beam electricity back to Earth without the use of cables.

Solar Power Beaming Satellite Mitsubishi and IHI are joining a research group containing 14 other countries to tackle the daunting task of getting Japan’s four square kilometer solar space station up and running in the next three decades. By 2015, the Japanese government hopes to test a small satellite decked out with solar panels that beams power through space and back to Earth.

via Inhabitat » Japan Plans $21 Billion Solar Space Post to Power 294,000 Homes.

The Recent Future / September 2, 2009 / Tech / 0 Comments

Tasting the Light: Device Lets the Blind “See” with Their Tongues

Neuroscientist Paul Bach-y-Rita hypothesized in the 1960s that “we see with our brains not our eyes.” Now, a new device trades on that thinking and aims to partially restore the experience of vision for the blind and visually impaired by relying on the nerves on the tongue’s surface to send light signals to the brain.

See with your toung!From the CPU, the signals are sent to the tongue via a “lollipop,” an electrode array about nine square centimeters that sits directly on the tongue. Each electrode corresponds to a set of pixels. White pixels yield a strong electrical pulse, whereas black pixels translate into no signal. Densely packed nerves at the tongue surface receive the incoming electrical signals, which feel a little like Pop Rocks or champagne bubbles to the user.

It remains unclear whether the information is then transferred to the brain’s visual cortex, where sight information is normally sent, or to its somatosensory cortex, where touch data from the tongue is interpreted, Wicab neuroscientist Aimee Arnoldussen says. “We don’t know with certainty,” she adds.

via Tasting the Light: Device Lets the Blind “See” with Their Tongues: Scientific American.

The Recent Future / August 23, 2009 / Health, SciFi, Tech / 0 Comments

DNA Evidence Can Be Fabricated, Scientists Show

Scientists in Israel have demonstrated that it is possible to fabricate DNA evidence, undermining the credibility of what has been considered the gold standard of proof in criminal cases.

The scientists fabricated blood and saliva samples containing DNA from a person other than the donor of the blood and saliva. They also showed that if they had access to a DNA profile in a database, they could construct a sample of DNA to match that profile without obtaining any tissue from that person.

“You can just engineer a crime scene,” said Dan Frumkin, lead author of the paper, which has been published online by the journal Forensic Science International: Genetics. “Any biology undergraduate could perform this.”

Dr. Frumkin is a founder of Nucleix, a company based in Tel Aviv that has developed a test to distinguish real DNA samples from fake ones that it hopes to sell to forensics laboratories.

The planting of fabricated DNA evidence at a crime scene is only one implication of the findings.

A potential invasion of personal privacy is another. Using some of the same techniques, it may be possible to scavenge anyone’s DNA from a discarded drinking cup or cigarette butt and turn it into a saliva sample that could be submitted to a genetic testing company that measures ancestry or the risk of getting various diseases. Celebrities might have to fear “genetic paparazzi,” said Gail H. Javitt of the Genetics and Public Policy Center at Johns Hopkins University.

via DNA Evidence Can Be Fabricated, Scientists Show –

The Recent Future / August 18, 2009 / SciFi, Tech / 0 Comments

‘Repulsive’ Side To Light Force Could Control Nanodevices

A team of Yale University researchers has discovered a “repulsive” light force that can be used to control components on silicon microchips, meaning future nanodevices could be controlled by light rather than electricity.

The attractive and repulsive light forces Tang’s team discovered are separate from the force created by light’s radiation pressure, which pushes against an object as light shines on it. Instead, they push out or pull in sideways from the direction the light travels.

via ‘Repulsive’ Side To Light Force Could Control Nanodevices.

The Recent Future / July 15, 2009 / SciFi, Tech / 0 Comments

UQ researchers break the law – of physics – UQ News Online – The University of Queensland

Two UQ Science researchers have proved two famous physical laws that have been widely used for the past 25 years do not always work.

Dr Tony Roberts and PhD student Christophe P. Haynes, from the School of Maths and Physics, showed the fractal-Einstein and Alexander-Orbach laws can fail in some instances, and have derived a new law to replace them.

Dr Roberts said this new discovery had implications for predicting material properties; how disease spreads through society; mapping how wild animals forage for food; and improving the internet.

“We demonstrated unequivocally that two ‘exact’ foundational laws of fractal science, which have been cited over 2000 times in the scientific literature, can fail for a class of fractals,” he said.

via UQ researchers break the law – of physics – UQ News Online – The University of Queensland.

The Recent Future / July 6, 2009 / Tech / 0 Comments

‘Cloak of silence’ tech could hide submarines –

A new invisibility cloak for sound could help doctors find tiny tumors or hide submarines from enemy sonar.

“Our focus is not about dampening noise, but to guide sound waves around structures,” said Nicholas Fang, a professor a the University of Illinois at Urbana Champaign and coauthor, along with Shu Zhang and Leilei Yin, on a paper that appears in the journal Physical Review Letters.

For example, “if we have a coating on a submarine that bends acoustics waves before they hit the surface, guiding them around the submarine smoothly, then you won’t be able to detect a submarine using sonar.”

The same technology that could render a military submarine invisible to sonar could also be used to create high-definition, in-utero baby pictures or detect previously undetectable, tiny tumors.

via ‘Cloak of silence’ tech could hide submarines –

The Recent Future / June 18, 2009 / Tech / 0 Comments

The Recent Future / June 15, 2009 / Tech / 0 Comments

Quantum Leap in Lighting

Seth Coe-Sullivan flicks the switches on two desk lamps, and even from across the conference room, it’s immediately obvious which light the chief technology officer of QD Vision is there to brag about. The light coming from the lamp on the left is a harsh bluish white. The lamp on the right casts a warmer, more yellow glow. Coe-Sullivan holds a hand under each lamp. The hand under the bluish light looks pale and sickly; the other looks darker and healthier. The harsher light lacks wavelengths in the red end of the spectrum, so there’s no light to illuminate the reddish tinge that blood provides to human skin.

QD Vision, based in Watertown, MA, is promoting a new LED-based lamp that it made with Nexxus Lighting of Charlotte, NC. Nexxus makes a lamp designed to screw into standard sockets used in recessed ceiling lighting. It consists of an array of white-light LEDs encircled by fins that remove excess heat. QD Vision adds an optic–a plastic cover with a special coating that snaps into place over the LEDs.

The Recent Future / June 15, 2009 / Tech / 0 Comments

The Recent Future / May 14, 2009 / Tech / 0 Comments