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Acoustic Hyperlens Could Sharpen Ultrasound Imaging

Metamaterial-based device demonstrates focusing of sound beyond its diffraction limit

3 min read

26 October 2009—In the past few years, researchers have created artificial materials known as metamaterials, which bend and focus light in unnatural ways. While a microscope's glass lens can detect only objects larger than half a wavelength of light, metamaterials could enable ultrahigh-resolution imaging of much tinier features.

A new device made by researchers at the University of California, Berkeley, does a similar trick with sound waves. Just as with its optical counterpart, imaging with sound is limited by the wave's length, a phenomenon called the diffraction limit. But the acoustic metamaterial that mechanical engineering professor Xiang Zhang and his colleagues presented yesterday on the online version of the journal Nature Materials magnifies and detects features that are just one-seventh of the sound signal's wavelength.

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Are You Ready for Workplace Brain Scanning?

Extracting and using brain data will make workers happier and more productive, backers say

11 min read
A photo collage showing a man wearing a eeg headset while looking at a computer screen.
Nadia Radic

Get ready: Neurotechnology is coming to the workplace. Neural sensors are now reliable and affordable enough to support commercial pilot projects that extract productivity-enhancing data from workers’ brains. These projects aren’t confined to specialized workplaces; they’re also happening in offices, factories, farms, and airports. The companies and people behind these neurotech devices are certain that they will improve our lives. But there are serious questions about whether work should be organized around certain functions of the brain, rather than the person as a whole.

To be clear, the kind of neurotech that’s currently available is nowhere close to reading minds. Sensors detect electrical activity across different areas of the brain, and the patterns in that activity can be broadly correlated with different feelings or physiological responses, such as stress, focus, or a reaction to external stimuli. These data can be exploited to make workers more efficient—and, proponents of the technology say, to make them happier. Two of the most interesting innovators in this field are the Israel-based startup InnerEye, which aims to give workers superhuman abilities, and Emotiv, a Silicon Valley neurotech company that’s bringing a brain-tracking wearable to office workers, including those working remotely.

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