Fig. 5

Wirelessly powered epidermal electronic systems. a Images of a stretchable epidermal electronic system that includes interconnected commercial chips in a closed microfluidic space for a fully wireless EP sensor, with an example of the device on the forearm, in compressed and twisted states (center). Representative ECG data show the expected waveforms collected with the device integrated on the sternum. Reprinted with permission from Xu et al.⁸² Copyright 2014 American Association for the Advancement of Science. b Image of a wireless stretchable optoelectronic system mounted on the forearm and its operating principle (left). Time-domain near-IR (NIR) spectroscopy data simultaneously recorded by a commercially available oximetry device (center) and a wireless epidermal oximetry device (right) laminated onto the adjacent locations of forearm. Reprinted with permission from Kim et al.⁸⁴ Copyright 2016 American Association for the Advancement of Science. c Image of a wireless epidermal battery-integrated system with temperature sensing/data processing (left). Images of the devices placed onto the forearm during exercise (center). Plots of temperature obtained by both an epidermal NFC device without a battery (AMS NFC) and a battery-integrated epidermal NFC device (TI NFC) (top right). Corresponding IR images show the responses from each stage of the evaluation (bottom right). Reprinted with permission from Lee et al.⁸⁵ Copyright 2016 National Academy of Sciences