Comparison of various wearable electronics. Rigid electronics. Upper left: dry and wireless EEG system. Reproduced with permission.[1]Copyright 2020, Springer Nature. Upper right: electrodes were attached near the inner and outer corners of the eye to measure EOG signals. Reproduced with permission.[2]Copyright 2017, Springer-Verlag Berlin Heidelberg. Lower left: a standard surface sensor was attached to the distal aspect of the right shin to determine foot contact. Reproduced with permission.[3]Copyright 2020, Elsevier Ltd. Lower right: photograph of lightweight and versatile hand exoskeleton. Reproduced with permission.[4]Copyright 2015, De Gruyter. Soft electronics. Upper left: electrode tattoo array attached to the cheeks. Reproduced with permission.[5]Copyright 2018, Springer Nature. Upper right: photograph of nanomesh sensors attached to the face. Reproduced with permission.[6]Copyright 2020, Advancement of Science. Lower left: photograph of wearable iontophoretic biosensor device on a printed tattoo platform. Reproduced with permission.[7]Copyright 2018, Wiley-VCH. Lower right: photographs show the flexible, wearable wireless-charging power system. Reproduced with permission.[8]Copyright 2024, American Chemical Society. Unperceivable electronics. Upper left: photographs of a human female subject wearing the soft, smart contact lens. Reproduced with permission.[33]Copyright 2021, Advancement of Science. Upper right: sweat collection patch attached to the human forehead. Reproduced with permission.[34]Copyright 2022, Elsevier Ltd. Lower left: photography of the pressure sensor on a fingertip. Reproduced with permission.[35]Copyright 2020, Springer Nature. Lower right: photograph of wearer wearing a cloth with sensor. Reproduced with permission.[36]Copyright 2020, Springer Nature.
