'New tattoo-like skin device to monitor your health'

Scientists have developed a new tattoo-like monitoring device that can be fixed on the skin like a patch and can detect skin temperature, sun exposure, heart rate, changes in skin colour and blood oxygen level.
The tiny ultra-thin device does not require any batteries to work. It captures the small amount of energy emitted by a smartphone or tablet that makes use of near-field communications (NFC).
NFC is a type of technology that employs electromagnetic induction between antennae inside of portable devices.
Radio frequencies are used to send information, which could be used as an energy source, making the use of a battery unnecessary, researchers including John Rogers from University of Illinois in the US said.

The device, which is no thicker than a sticker, is flexible and sticks to the skin, and collects information about the body that is then transmitted wirelessly to a nearby device, 'Techxplore' reported.
The monitor has light-emitting diodes (LEDs) on the skin side. The light reflected back is used to measure heart rate, changes to skin colour and oxygenation levels, researchers said.

The device also has a dye-based light sensor which measures ultraviolet light and another sensor that monitors skin temperature.
According to researchers, the device will be useful in health-care facilities and ultimately to the population at large.
The findings were published in the journal Science Advances.