WHAT GOES AROUND: An ongoing problem with solar cells is their low efficiency. Researchers at the University of California have shown that solar cells that emit light as well as absorb it can be more efficient than those that don't emit light. They demonstrated that the better a solar cell is at emitting photons, the higher its voltage. The researchers say there's a thermodynamic link between absorption and emission that produces this unusual effect. Or maybe it's just the pay it forward principle. Visit The Optical Society.
HANDS-ON MAP: Systems developed to help robots navigate could be used to help blind people. Researchers at at the Pierre and Marie Curie University in France created a pair of glasses equipped with cameras and sensors such as accelerometers and gyroscopes. The system produces a 3D map of the wearer's environment and their position within it in real-time then feeds the map to a handheld electronic Braille device. The Braille map is updated fast enough for the user to walk through an area.