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A Form-fitting Photovoltaic Artificial Retina

Retina chip gets both power and data from near-infrared light

4 min read

22 December 2009—Several teams of scientists and engineers have been trying for years to produce a practical retinal prosthesis for people afflicted by a progressive loss of photoreceptor cells. One problem all the researchers face is how to get power and data (the image) to a retinal chip that’s implanted at the back of a person’s eye. Some groups’ implants, such as those from the University of Southern California’s Doheny Eye Institute and an MIT-Harvard team get their power and data from RF signals beamed in from the outside, while other groups, including one at the University Eye Hospital in Tübingen, Germany, are working on getting the data as light entering the eye using RF energy to beam in the power. But a team from Stanford University has been working on what might seem like the obvious solution: using light entering the eye for both power and data.

The Stanford implant is designed as an array of miniature solar cells. The device—technically a subretinal implant, because it is placed behind the retina—is part of a system that includes a video camera that captures images, a pocket PC that processes the video feed, and a bright near-infrared LCD display built into video goggles. The pulsed 900-nanometer-wavelength image that shines into the eyes is enough to produce electricity in the chip. (A chip driven by just the ambient light coming in to your eye would produce current that is one-thousandth or less the strength required to trigger retinal neurons.) The researchers chose a near-infrared display because it is invisible. Some patients’ retinas might still have some working photoreceptors that could be stimulated by visible light. Visible light bright enough to stimulate cells would yield artifacts that would muddy the image generated in the brain.

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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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