Abstract
This study presented a wireless smart contact lens system that was composed of a reconfigurable capacitive sensor interface circuitry and wirelessly powered radio-frequency identification (RFID) addressable system for sensor control and data communication. In order to improve compliance and reduce user discomfort, a capacitive sensor was embedded on a soft contact lens of 200 μm thickness using commercially available bio-compatible lens material and a standard manufacturing process. The results indicated that the reconfigurable sensor interface achieved sensitivity and baseline tuning up to 120 pF while consuming only 110 μW power. The range and sensitivity tuning of the readout circuitry ensured a reliable operation with respect to sensor fabrication variations and independent calibration of the sensor baseline for individuals. The on-chip voltage scaling allowed the further extension of the detection range and prevented the implementation of large on-chip elements. The on-lens system enabled the detection of capacitive variation caused by pressure changes in the range of 2.25 to 30 mmHg and hydration level variation from a distance of 1 cm using incident power from an RFID reader at 26.5 dBm.
Highlights
An increase in on-lens sensors presents an attractive proposition to maximize the procurement of eye health information to the maximum possible extent
Intraocular pressure (IOP) measurement for glaucoma prevention was used to illustrate the functionality of the proposed smart contact lens (SCL) system in the study
Conclusions to communicate with commercial Gen2 radio-frequency identification (RFID)-compatible equipment to demonstrate periodical IOP
Summary
Jin-Chern Chiou 1,2 , Shun-Hsi Hsu 1, *, Yu-Chieh Huang 2 , Guan-Ting Yeh 2 , Wei-Ting Liou 2 and. Received: 14 November 2016; Accepted: 30 December 2016; Published: 7 January 2017
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
