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Title: Power Scavenging Microsystem for Smart Contact Lenses
Abstract On‐the‐eye microsystems such as smart contacts for vision correction, health monitoring, drug delivery, and displaying information represent a new emerging class of low‐profile (≤ 1 mm) wireless microsystems that conform to the curvature of the eyeball surface. The implementation of suitable low‐profile power sources for eye‐based microsystems on curved substrates is a major technical challenge addressed in this paper. The fabrication and characterization of a hybrid energy generation unit composed of a flexible silicon solar cell and eye‐blinking activated Mg–O2metal–air harvester capable of sustainably supplying electrical power to smart ocular devices are reported. The encapsulated photovoltaic device provides a DC output with a power density of 42.4 µW cm−2and 2.5 mW cm−2under indoor and outdoor lighting conditions, respectively. The eye‐blinking activated Mg–air harvester delivers pulsed power output with a maximum power density of 1.3 mW cm−2. A power management circuit with an integrated 11 mF supercapacitor is used to convert the harvesters’ pulsed voltages to DC, boost up the voltages, and continuously deliver ≈150 µW at a stable 3.3 V DC output. Uniquely, in contrast to wireless power transfer, the power pack continuously generates electric power and does not require any type of external accessories for operation.  more » « less
Award ID(s):
1932602
PAR ID:
10499270
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Small
ISSN:
1613-6810
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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