engineer helps pioneer flat spray-on optical lens
Kenneth Chau is excited about the newly published research that explains how he and his colleagues developed a negative-index material that can be sprayed onto surfaces and act as a lens. A team of researchers, including a University of British Columbia engineer have made a breakthrough utilizing spray-on technology that could revolutionize the way optical lenses are made and used. Kenneth Chau, an assistant professor in the School of Engineering at UBC’s Okanagan campus,worked with principal investigator Henri Lezec and colleagues Ting Xu, Amit Agrawal, and Maxim Abashin at the National Institute of Standards and Technology in Maryland on the development of a flat lens. Their work is published in the May 23 issue of the journal Nature. Nearly all lenses – whether in an eye, a camera, or a microscope – are presently curved, which limits the aperture, or amount of light that enters. “Curved lenses always have a limited aperture,” he explains. NB: An image of Prof.
Sprinkled nanocubes hold light tight
Cristian Ciraci Scattering silver nanocubes over a metallic film may help harvest the sun's rays. Just sprinkle on and harvest light — that is the procedure with nanoscale cubes of silver that could be used to make efficient solar panels, heat detectors and specialist cameras. The cubes are scattered randomly on a piece of polymer-coated metal to form a device that absorbs nearly all the light that hits it. The material, which can be tuned to ensnare the desired wavelength of light, is described today in Nature1. Trapped in a gap Absorbers that can capture all, or almost all, of the light that hits them are typically made with metamaterials — materials engineered to have particular properties not found in nature. These minuscule components are painstakingly fabricated in a laborious, expensive etching process using lithography, so the light absorbers are difficult to make in large quantities. Smith and his team took a different approach. Different wavelengths
University - Tiny structure gives big boost to solar power
Posted December 6, 2012; 03:30 p.m. by John Sullivan, Office of Engineering Communications Princeton researchers have found a simple and economical way to nearly triple the efficiency of organic solar cells, the cheap and flexible plastic devices that many scientists believe could be the future of solar power. The researchers, led by electrical engineer Stephen Chou, were able to increase the efficiency of the solar cells 175 percent by using a nanostructured "sandwich" of metal and plastic that collects and traps light. Chou said the technology also should increase the efficiency of conventional inorganic solar collectors, such as standard silicon solar panels, although he cautioned that his team has not yet completed research with inorganic devices. Chou, the Joseph C. With their new metallic sandwich, the researchers were able to address both problems. That is for direct sunlight. The physics behind the innovation is formidably complex. "It is like a black hole for light," Chou said.
MIT’s sun funnel could slit solar power’s efficiency bottleneck
Every day, our Sun beats more energy into the world’s deserts than is used by the entire human race in a year. Every joule of energy in the world’s oil reserves was put there by the sun, millions of years ago. Even uranium was created in the death-rattle explosion of some ancient star. We have found or developed hundreds of middle-men, from coal turbines to AAA batteries, energy carriers who power up on star energy and release it only grudgingly to human beings. The flaw in solar power has always been efficiency. Ergon Energy Station in Windorah, Australia Until now. This neatly sidesteps the major problem with collection of solar energy: there’s so much of it. A solar funnel, as proposed by MIT, could catch many different wavelengths of light all along its surface — and unlike modern organic cells, which rely on diffusion to bring excited units to the collector, this one would direct every captured photon quickly down toward the collector.
