Fig. 3: A variety of NFC/RFID-based contact lens designs with the ability to monitor IOP.

a Schematic illustration of the resistive wireless IOP sensing contact lens, and the equivalent circuit diagram⁵¹. Copyright 2020, ACS. b Schematic diagram of the capacitive smart contact lens and the reader integrated in the glasses⁵². Copyright 2022, ACS. c Schematic illustration of the mechanism by which an overall flexible contact lens measures IOP⁵³. Copyright 2017, Springer Nature. d Schematic illustration of the contact lens integration system with the introduction of NFC chip, the enlarged part is schematic illustration of the printed free-standing 3D interconnects on the metallic pads of an NFC chip². Copyright 2021, Springer Nature. e Closed-loop smart contact lens integrated with a flexible drug delivery system and a microchip, which are designed for the monitoring and control of IOP⁵⁴. Copyright 2022, Springer Nature