It sounds like something out of Star Trek: a patch thinner than a band-aid that you slap on your arm and, within moments, it lights up with heart rate, blood sugar, and so on — then peels off a few days later. That’s the goal of work by researchers at the University of Tokyo, who have invented an ultra-thin “E-skin” that can protect flexible electronics and make things like on-skin displays possible.
Electronics have been stuck to the skin before, of course, or drawn on with conductive ink, but even substrates just a millimeter thick are limited in flexibility. The research headed by Takao Someya and Tomoyuki Yokota drops that thickness by an order of magnitude.

The displays shown above are proof of the concept: they require electrodes instead of being powered by body heat or flexible batteries, and of course don’t actually read anything just yet.
“What would the world be like if we had displays that could adhere to our bodies and even show our emotions or level of stress or unease?” asks Someya in a news release accompanying the paper, which was published Friday in Science Advances.
Probably very creepy. But there are also tons of legitimate medical and consumer applications towards which research like this advances us.
