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Wireless Display on a Contact Lens

Researchers demonstrate the ability to remotely power and control a single pixel, and say multi-pixel arrays are on the way

2 min read
Wireless Display on a Contact Lens

 

A team of researchers led by Babak Amir Parviz, an associate professor of electrical engineering at the University of Washington, just published a paper in the 22 November edition of the Journal of Micromechanics and Microengineering that described a breakthrough in the development of an electronic contact lens with a built-in display. Parviz, who collaborated with University of Washington ophthalmologist Tueng Shen and optoelectronics researchers from Aalto University in Finland, has for several years been working on contact lenses that will someday augment the wearer’s vision with external data or use sensors to collect data about the state of the wearer’s health.

The researchers say that they successfully created a single-pixel wireless display comprising a blue gallium nitride LED mounted on a transparent sapphire chip, an integrated circuit that doubles as a power harvester and controller for the LED, and metal interconnects. They also showed that a series of passive lenses (called Fresnel lenses) less than 1 micrometer thick, when placed on the surface of the contact lens about 360 micrometers away from the LED, can focus the LED light onto the retina in a way that makes it appear as though the single-pixel image is floating in space about 1 meter away from the eye.  Otherwise, the image would be right up against the cornea, where the human eye is incapable of bringing objects into focus.

Of the high-tech miniature display, the researchers said that although it has only one controllable pixel, “…we have provided the first proof-of-concept technology demonstrations for producing multipixel and in-focus images using a contact lens by producing multipixel micro-LED array chips on transparent substrates and micrometer-scale Fresnel lenses that can be integrated into a contact lens.” In other words, the team is making significant progress toward the goal—an array of 3600 10-µm-wide pixels spaced 10 µm apart—that Parviz mentioned in the September 2009 IEEE Spectrum article “Augmented Reality in a Contact Lens.” Now that the researchers have demonstrated the ability to remotely control red and blue LEDs, doing so with green ones is the next step in order to produce full-color displays integrated into contact lenses.

Among the technical hurdles that remain is developing an improved power supply. The 5-millimeter-radius loop antenna used to draw power wirelessly in the experiments documented in the paper only harvests enough energy when it is within about 2 centimeters of the radio transmitter. Another problem is that the so-called bionic lens is made from polyethylene terephthalate, a form plastic that is not porous enough to be worn against the eye all day. Its poor oxygen permeability could lead to corneal swelling. But the team says it is already back in the lab, attempting to overcome these challenges.

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