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Color-changing temporary tattoo reveals when you’ve soaked up too much sun

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From smartphone apps to smart wearables, there are a variety of high-tech ways we can make sure we’re not being exposed to too many harmful ultraviolet wavelengths by being out in the sun. A new creation from San Francisco-based LogicInk promises to make things even easier, however. Instead of asking users to whip out their phones to check information about UV exposure, LogicInk has developed a small temporary tattoo, worn on your skin, that changes color as it’s exposed to sunlight. What could be simpler than that?

“Based on medical research, LogicInk UV is calibrated to change in shape and color to alert you when you got too much [sun] for the day,” Carlos Olguin, co-founder and CEO of LogicInk, told Digital Trends. “We are initially focusing on people with very sensitive skin. By precluding electronics, we also preclude the need for bulky devices — bulky compared to ours — that tend to be expensive, have a high learning curve, and yet require another device as the only way to understand your exposure to UV.”

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It’s a neat design, and promises to offer at-a-glance information about this important topic. The tattoo features a design created from proprietary inks, and gradually changes from white to purple based on the wearer’s exposure to the sun. The design features several rings, each of which changes color in turn based on cumulative exposure. Once all three have gone purple, users know that they have hit their UV limit for the day.

Image used with permission by copyright holder

“LogicInk UV allows people from all ages to intuitively understand when UV rays may becoming harmful and take action,” Olguin said. “The tattoo is the user interface. We are reusing and reinventing user interface patterns like energy bars in an LCD display, but now placing them directly on your skin, where they change dynamically when sensing occurs. We are programming apps directly in matter.”

Olguin says that the team expects to launch LogicInk UV in time for this summer. One tattoo can last for up to one week, although he notes that the “user interface” makes more sense as a daily measure, so he suggests single-day use. “We are still exploring what is the best way to sell LogicInk UV,” he continued. “Ordering a regular supply is one of them.”

If you want to try one out before then, LogicInk is currently running a beta program where people can test LogicInk UV for a period of days or weeks. Anyone interested can visit the company’s website and sign up to be notified about this program or to receive news regarding the launch.

Luke Dormehl
I'm a UK-based tech writer covering Cool Tech at Digital Trends. I've also written for Fast Company, Wired, the Guardian…
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