A disposable reader-sensor solution for wireless temperature logging

초록

Wireless passive sensors, being battery-free and simple, are suitable for disposable use across various applications, from tracking food and monitoring the environment to clinical diagnostics. However, their utilization is hampered by the complexity of existing readout techniques and the absence of memory functionality within the sensor. Here, we present a reader technique that can automatically lock to the sensor value wirelessly through inductive coupling, significantly reducing the reader complexity. By integrating a high-frequency audio link and wireless powering, we demonstrate a battery-free and flexible reader. We integrated this reader for wireless temperature logging, which logs temperature data based on the irreversible geometric change of low-melting-point metal during phase transitions, resulting in non-volatile resistance change. As a whole, these results establish the feasibility of a simplistic reader and a passive non-volatile thermistor sensor, opening up new possibilities for disposable and ubiquitous temperature monitoring as well as a range of other applications.

키워드