http://www.sciencedaily.com/news/matter_energy/nature_of_light/ Optics. Can light go backwards? Researchers push the limits of our understanding of light. Also see amazing new applications of light energy. Full-text, images, free. en-us Mon, 12 May 2008 21:05:01 EDT Mon, 12 May 2008 21:05:01 EDT 60 http://www.sciencedaily.com/images/logosmall.gif http://www.sciencedaily.com/news/matter_energy/nature_of_light/ For more science articles, visit ScienceDaily. http://www.sciencedaily.com/releases/2008/05/080508151505.htm Lasers that emit ultrashort pulses of light are used for numerous applications, but the quality of the results is limited by distortions caused by lenses and other optical components that are part of the experimental instrumentation. Researchers have developed a system that tells researchers what types of aberrations are present, which allows them to create the desired pulse at the focus that's free of distortions. Tue, 13 May 2008 08:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080508151505.htm http://www.sciencedaily.com/releases/2008/05/080512172317.htm Plants have an ambivalent relationship with light. They need it to live, but too much light leads to the increased production of high-energy chemical intermediates that can injure or kill the plant. The intermediates do this because the efficient conversion of sunlight into chemical energy cannot keep up with sunlight streaming into the plant. Tue, 13 May 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080512172317.htm http://www.sciencedaily.com/releases/2008/05/080512124408.htm Satellites taking atmospheric measurements might now be able to see blue skies as clearly as optimists do. Researchers have found a way to reduce cloud-induced glare when satellites measure blue skies on cloudy days, by as much as ten-fold in some cases. The result might lead to more accurate estimates of the amount of sunlight penetrating the atmosphere. Because clouds represent one of the largest areas of uncertainty, eventually this could lead to improved climate models. Mon, 12 May 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080512124408.htm http://www.sciencedaily.com/releases/2008/05/080511094422.htm Hospital cleaners should watch out because the toilet police are patrolling with their new secret weapon: invisible markers. A team of Canadian scientists using a lotion which glows under ultraviolet light have shown that up to a third of patient toilets are not properly cleaned. Their findings, also show that spores from the nasty bacteria Clostridium difficile (C. difficile) linger in the loo even when it has been thoroughly wiped down. Mon, 12 May 2008 11:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080511094422.htm http://www.sciencedaily.com/releases/2008/05/080508145501.htm Now that the genome of humans and many other organisms have been sequenced, biologists are turning their attention to discovering how the many thousands of structural and control genes -- the "worker bees" of living cells that can turn genes on and off -- function. Mon, 12 May 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080508145501.htm http://www.sciencedaily.com/releases/2008/05/080508164412.htm Scientists have developed a new technique for fabricating nanowire photonic and electronic integrated circuits that may one day be suitable for high-volume commercial production. The fabrication technique could yield low-cost, scalable nanowire photonic and electronic circuits. Sun, 11 May 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080508164412.htm http://www.sciencedaily.com/releases/2008/05/080508100718.htm How does light pass through a tiny hole? For the first time, scientists have succeeded in mapping this process in detail. Their research also promises a significant improvement in Terahertz microscopy in the long term, a potentially interesting new imaging technique, and Terahertz microspectroscopy, a technique for identifying tiny quantities of substances using light. Sat, 10 May 2008 08:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080508100718.htm http://www.sciencedaily.com/releases/2008/05/080506103722.htm An innovative laser treatment for early vocal-cord cancer successfully restores patients' voices without radiotherapy or traditional surgery, which can permanently damage vocal quality. Wed, 07 May 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080506103722.htm http://www.sciencedaily.com/releases/2008/05/080504153803.htm As microchips shrink, even tiny defects in the lines, dots and other shapes etched on them become major barriers to performance. Princeton engineers have now found a way to literally melt away such defects, using a process that could dramatically improve chip quality without increasing fabrication cost. Mon, 05 May 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080504153803.htm http://www.sciencedaily.com/releases/2008/05/080505074759.htm As many parents know, it's often easier to keep your kids under control by exerting less authority rather than more. A child who fidgets uncontrollably in a confining booster seat, for example, may be perfectly content on a plain old chair. Physicists have found that the same is true in controlling the movement of particles suspended in liquids. What's more, they speculate that many microscopic systems, macroscopic ecosystems, and human social systems may respond to a gentle touch for the very same mathematical reasons. Mon, 05 May 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080505074759.htm http://www.sciencedaily.com/releases/2008/05/080502110829.htm Reading about a "random laser" for the first time, you might wonder whether this term refers to the laser in your CD player which plays the song titles in the random shuffle mode. In physics, however, "random lasers" refer to a class of microlasers which use the principle of random light scattering as an integral part of the laser operation. In conventional lasers light is trapped between two highly reflecting mirrors where it is amplified by pumping from outside. Only when this amplification process is efficient enough, the laser begins to operate. Mon, 05 May 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/05/080502110829.htm http://www.sciencedaily.com/releases/2008/04/080429170954.htm Researchers believe they can achieve a significant increase in the accuracy of one of the fundamental constants of nature by boosting an electron to an orbit as far as possible from the atomic nucleus that binds it. The experiment could put the modern theory of the atom to the most stringent tests yet. Thu, 01 May 2008 02:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080429170954.htm http://www.sciencedaily.com/releases/2008/04/080430134238.htm Scientists from Arizona State University and the University of Oxford, whose work appears in the April 30 advanced online publication of the journal Nature, have synthesized and studied a sophisticated molecule that, under illumination, is sensitive to both the magnitude and the direction of magnetic fields as tiny as the Earth's, which is, on average, one-twenty thousandth as strong as a refrigerator magnet. Wed, 30 Apr 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080430134238.htm http://www.sciencedaily.com/releases/2008/04/080427194715.htm A new technique that marries a fast-moving laser beam with a special microscope that look at tissues in different optical planes will enable scientists to get a 3-D view of neurons or nerve cells as they interact. A multiphoton microscope looks much like a conventional, upright microscope but it has an adaption that allows it to look at tissues in sections. Wed, 30 Apr 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080427194715.htm http://www.sciencedaily.com/releases/2008/04/080428164259.htm An advance by physicists improves our understanding of how light interacts with matter, and could make possible the development of new integrated-circuit technologies that result in faster computers that use less energy. Wed, 30 Apr 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080428164259.htm http://www.sciencedaily.com/releases/2008/04/080428085757.htm Imagine a technology that would not only provide a green and renewable source of electrical energy, but could also help scrub the atmosphere of excessive carbon dioxide resulting from the burning of fossil fuels. That's the promise of artificial versions of photosynthesis, the process by which green plants have been converting solar energy into electrochemical energy for millions of years. The first direct experimental links between atomic and electronic structures in pigment-protein complexes while energy is being transferred during photosynthesis have been attained. Mon, 28 Apr 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080428085757.htm http://www.sciencedaily.com/releases/2008/04/080416104314.htm Today, complex optical free-form geometries are used primarily in car headlamps and in optics for cameras and digital projectors. These optical components are expensive to manufacture and to test. A new 3-D measuring system LensShape renders the manufacturing process faster and more cost-effective. Mon, 28 Apr 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080416104314.htm http://www.sciencedaily.com/releases/2008/04/080427194738.htm Researchers from the Universities of Exeter and Coventry have developed the first new technique for diagnosing malaria able to challenge the rapid diagnostic tests currently used in the field. Early results suggest that the technique could be as effective as RDTs but far faster and cheaper. The team is now working on a noninvasive version of the device, which it plans to trial in Kenya later this year. Mon, 28 Apr 2008 02:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080427194738.htm http://www.sciencedaily.com/releases/2008/04/080424103646.htm The goal of replacing electronics with optics for processing data in computers is coming closer through cutting-edge European research into the mysterious properties of "fast and slow" light. The long-term aim is to boost processing speeds and data storage densities by several orders of magnitude and take the information technology industry into a new era, combining greatly improved performance with dramatically lower energy consumption. Sun, 27 Apr 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080424103646.htm http://www.sciencedaily.com/releases/2008/04/080421170215.htm The standard eye chart only covers letters and numbers, but athletes need above average vision to track balls hurtling toward them at alarming speeds. To test those special skills, optometrist will have athletes perform while a strobe light is flashing, play tag with a board of lights and engage in other activities designed to improve their visual abilities. Fri, 25 Apr 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080421170215.htm http://www.sciencedaily.com/releases/2008/04/080422155735.htm The microscopic structure of the human brain is almost incomprehensibly complicated, composed of trillions of interconnections between tens of billions of neurons. Understanding this circuitry, the aim of modern neuroscience, is a laudable goal for fundamental as well as neurological health care reasons. Exploring the brain's microcircuitry has traditionally been done by lining up tiny electrodes within or near single neurons to probe their electrical activity. Fri, 25 Apr 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080422155735.htm http://www.sciencedaily.com/releases/2008/04/080422155058.htm Early miners used to carry canaries into coal mines because the birds were sensitive to certain gasses. Modern chemical analysis does the same thing, though much more powerfully. For instance, infrared spectroscopy can detect even trace amounts of a wide range of chemicals, including toxic components of hazardous waste or chemical weapons, because many chemicals absorb light in the mid-infrared band. Fri, 25 Apr 2008 02:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080422155058.htm http://www.sciencedaily.com/releases/2008/04/080422123058.htm Chemical engineers have developed a "self-assembling" method that could lead to an inexpensive way of making diamondlike crystals to improve optical communications and other technologies. Wed, 23 Apr 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080422123058.htm http://www.sciencedaily.com/releases/2008/04/080422160001.htm The exchange of information between distant sources is the basis of all communications, but quantum mechanics may open up this distant exchange as never before. Quantum key distribution, for instance, would allow for absolutely secure encryption of information exchange by encoding information keys on single photons. Wed, 23 Apr 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080422160001.htm http://www.sciencedaily.com/releases/2008/04/080422160243.htm Silicon is the workhorse among semiconductors in electronics. But in opto-electronics, where light signals are processed along with electronic signals, a semiconductor that is capable of emitting light is needed, which silicon can't do very well. Here gallium-arsenide (GaAs) is the workhorse, especially in the creation of light emitting diodes (LED) and LED lasers. Scientists have now grown GaAs structures into the shape of narrow needles which, when optically pumped, emit light with high brightness. Wed, 23 Apr 2008 11:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080422160243.htm http://www.sciencedaily.com/releases/2008/04/080422103917.htm Scientists and engineers across Europe have joined forces in a unique collaborative effort to develop a new generation of high-brightness lasers that will transform the fields of healthcare, communications and entertainment. Tue, 22 Apr 2008 00:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080422103917.htm http://www.sciencedaily.com/releases/2008/04/080416114413.htm Securing evidence at the scene of a crime, measuring faces for medical applications, taking samples during production -- 3-D images are in demand everywhere. A handy cordless device now enables such images to be prepared rapidly anywhere. Mon, 21 Apr 2008 08:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080416114413.htm http://www.sciencedaily.com/releases/2008/04/080415185011.htm Computer scientists have created a fog and smoke machine for computer graphics that cuts the computational cost of making realistic smoky and foggy 3-D images, such as beams of light from a lighthouse piercing thick fog. By cutting the computing costs, the computer scientists are helping to pull cutting edge graphics techniques out of research labs and into movies and eventually video games and beyond. Sun, 20 Apr 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080415185011.htm http://www.sciencedaily.com/releases/2008/04/080415115349.htm They may never win an Oscar, but scientists have developed techniques for creating accurate movies of biological and chemical molecules, a feat only theorized up until now. Biological and organic molecules in solution are far more complex than the standard crystalline structures of salt or metals since they are constantly moving and changing over time. These motions have not yet been seen directly, but scientists using the high intensity x-rays at the Advanced Photon Source have measured images that are "blurred" by these motions and have used them to create more accurate movies of molecular motions. Thu, 17 Apr 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080415115349.htm http://www.sciencedaily.com/releases/2008/04/080415143816.htm Gravitational radiation -- widely expected to provide "smoking gun" proof for a theory of the early universe known as "inflation" -- can be produced by another mechanism, according to physics researchers. Thu, 17 Apr 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080415143816.htm http://www.sciencedaily.com/releases/2008/04/080415185016.htm A frequency-agile meta-material that for the first time can be tuned over a range of frequencies in the so-called "terahertz gap" has been engineered. The team's first-generation device achieved 20 percent tuning of the terahertz resonance to lower frequencies -- those in the far-infrared region -- addressing the critical issue of narrow band response typical of all metamaterial designs to date. Wed, 16 Apr 2008 08:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080415185016.htm http://www.sciencedaily.com/releases/2008/04/080414232716.htm Engineers took an early step toward building superfast computers that run on far-infrared light instead of electricity: They made waveguides -- the equivalent of wires -- that carried and bent this form of light, also known as terahertz radiation, which is the last unexploited portion of the electromagnetic spectrum. Tue, 15 Apr 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080414232716.htm http://www.sciencedaily.com/releases/2008/04/080414094152.htm The National Physical Laboratory is launching a revolutionary new measurement system that will bring laboratory level standards to the shop floor. The technology enables significantly improved calibration times and thereby, minimizes machine downtime for industries across the manufacturing sector. Tue, 15 Apr 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080414094152.htm http://www.sciencedaily.com/releases/2008/04/080410140451.htm By using a popcorn-ball design -- tiny kernels clumped into much larger porous spheres -- engineers can more than double the efficiency of a type of solar cell at converting the sun's rays to electricity. Tue, 15 Apr 2008 08:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080410140451.htm http://www.sciencedaily.com/releases/2008/04/080409205858.htm Detecting roadside bombs may become easier, thanks to chemical sensors under development. Chemists have created materials that sniff out TNT and give off signals that can be detected remotely -- from a moving Humvee, for example. Sun, 13 Apr 2008 20:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080409205858.htm http://www.sciencedaily.com/releases/2008/04/080409091733.htm Carbon nanotubes are promising materials for many high-technology applications due to their exceptional mechanical, thermal, chemical, optical and electrical properties. Now researchers have used metallic nanotubes to make thin films that are semitransparent, highly conductive, flexible and come in a variety of colors, with an appearance similar to stained glass. These results could lead to improved high-tech products such as flat-panel displays and solar cells. Thu, 10 Apr 2008 23:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080409091733.htm http://www.sciencedaily.com/releases/2008/04/080409150058.htm Researchers have discovered why rocket engines are occasionally destroyed by mysterious waves of sound. The new imaging techniques allow scientists to observe and understand the destructive waves. Thu, 10 Apr 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080409150058.htm http://www.sciencedaily.com/releases/2008/04/080408085449.htm The Texas Petawatt laser reached greater than one petawatt of laser power on Monday morning, March 31, making it the highest powered laser in the world. When the laser is turned on, it has the power output of more than 2,000 times the output of all power plants in the United States. Wed, 09 Apr 2008 08:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080408085449.htm http://www.sciencedaily.com/releases/2008/04/080408102830.htm Terahertz waves, which until now have barely found their way out of the laboratory, could soon be in use as a versatile tool. Researchers have mobilized the transmitting and receiving devices so that they can be used anywhere with ease. Everybody knows microwaves -- but what are terahertz waves? These higher-frequency waves are a real jack-of-all-trades. They can help to detect explosives or drugs without having to open a suitcase or search through items of clothing. They can reveal which substances are flowing through plastic tubes. They can penetrate wood, ceramics, paper, plastic or fabrics and are not harmful to humans. On the other hand, they cannot pass through metal. Wed, 09 Apr 2008 05:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080408102830.htm http://www.sciencedaily.com/releases/2008/04/080407153030.htm Fungi processing audio signals. E. Coli storing images. DNA acting as logic circuits. It's possible, and in some cases, it's already happened. In any event, performing digital signal processing using organic and chemical materials without electrical currents could be the wave of the future. Electrical engineers and computer science specialists describe experiments that perform signal processing with novel materials while stirring the engineering community towards "a possible not-so-electronic future" of digital signal processing. Tue, 08 Apr 2008 23:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080407153030.htm http://www.sciencedaily.com/releases/2008/04/080408144812.htm Escalating oil and gas prices along with the global challenge of climate change has in the past few years spurred a generation of scientists to pursue alternative energy sources while redirecting the focus away from fossil fuels. What is the current status, limitations and future challenges of alternative energy sources? Tue, 08 Apr 2008 00:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080408144812.htm http://www.sciencedaily.com/releases/2008/04/080402204950.htm You are driving in heavy traffic. The brake lights on the car in front of you come on. Is the car slowing or is it going to stop? It slows to 25 mph and the lights go off. You drop back. The car in front of you stops suddenly! You stop just in time. The car behind you collects your rear bumper. Mon, 07 Apr 2008 11:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080402204950.htm http://www.sciencedaily.com/releases/2008/04/080402100014.htm Scientists have succeeded in cooling atoms of a rare-earth element, erbium, to within two millionths of a degree of absolute zero using a novel trapping and laser cooling technique. Potential applications range from nanoscale sensors to quantum computing. Sat, 05 Apr 2008 14:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080402100014.htm http://www.sciencedaily.com/releases/2008/04/080401095236.htm A novel type of nanomachine that traps molecules such as anticancer drugs inside tiny pores and releases them inside cancer cells in response to light has been developed. It's the first light-powered nanomachine created that operates inside a living cell, a development that has strong implications for use in treating cancer. Wed, 02 Apr 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080401095236.htm http://www.sciencedaily.com/releases/2008/04/080401112407.htm A car that navigates city streets without a driver -- steered only by a computer? That might seem impossible to many. But researchers are presenting such an automated vehicle at this year's Hannover Messe in April. Its core element is a 3-D laser scanner. Wed, 02 Apr 2008 17:00:00 EDT http://www.sciencedaily.com/releases/2008/04/080401112407.htm http://www.sciencedaily.com/releases/2008/03/080331172528.htm Medical scientists have developed a new type of imaging system that can illuminate tumors in living subjects-getting pictures with a precision of nearly one-trillionth of a meter. Wed, 02 Apr 2008 11:00:00 EDT http://www.sciencedaily.com/releases/2008/03/080331172528.htm http://www.sciencedaily.com/releases/2008/03/080330212029.htm Researchers have observed, through a microscope, plasmons on the surface of conductors measuring 30 nanometers. The use of such plasmons, signals that are at the limit of electronics and optics, is becoming, on this scale, an important issue for the much sought-after miniaturization of electronic circuits. Tue, 01 Apr 2008 11:00:00 EDT http://www.sciencedaily.com/releases/2008/03/080330212029.htm http://www.sciencedaily.com/releases/2008/03/080330211108.htm Researchers have succeeded in synthesizing porous nanoparticles that are capable of absorbing the energy of two photons in the near infrared spectrum, and then re-emitting radiation used for medical imaging by fluorescence. These two-photon nanoparticles should enable the more precise detection of tumor cells and, in the longer term, better-targeted therapy. Tue, 01 Apr 2008 08:00:00 EDT http://www.sciencedaily.com/releases/2008/03/080330211108.htm