Transparent and flexible fingerprint sensor array with multiplexed detection of tactile pressure and skin temperature

Abstract

We developed a transparent and flexible, capacitive fingerprint sensor array with multiplexed, simultaneous detection of tactile pressure and finger skin temperature for mobile smart devices. In our approach, networks of hybrid nanostructures using ultra-long metal nanofibers and finer nanowires were formed as transparent, flexible electrodes of a multifunctional sensor array. These sensors exhibited excellent optoelectronic properties and outstanding reliability against mechanical bending. This fingerprint sensor array has a high resolution with good transparency. This sensor offers a capacitance variation ~17 times better than the variation for the same sensor pattern using conventional ITO electrodes. This sensor with the hybrid electrode also operates at high frequencies with negligible degradation in its performance against various noise signals from mobile devices. Furthermore, this fingerprint sensor array can be integrated with all transparent forms of tactile pressure sensors and skin temperature sensors, to enable the detection of a finger pressing on the display.

Ideas for how informaticians can get involved with COVID-19 research

“…Smartphones and other wearable smart devices contain research-grade sensors that are capable of shedding light on at least a subset of COVID-19 symptoms which include fever, fatigue, dry-cough, and shortness of breath. For example, the temperature recorded by fingerprint sensors, which are now standard on most modern smartphones, has previously been used to successfully predict fever [19]. In addition, activity sensors such as the accelerometer have been used to detect fatigue.…”

A Novel Fingerprint Sensing Technology Based on Electrostatic Imaging

“…Commonly used biometric methods include fingerprint recognition [3,4,5,6], iris recognition, and facial recognition [3,4]. Among them, fingerprint recognition is the most widely used biometric identification method.…”

“…The optical fingerprint sensor captures a fingerprint image through the lens and can penetrate thicker glass. Synopsys’ optical fingerprint sensor can be placed at the bottom of the screen, independent of the thickness of the glass, but at a higher cost and with limited security, it can be deceived by fingerprint images [3]. A fingerprint sensor based on thermal detection uses a thermoelectric material to measure the amount of heat transferred from the sensor to the fingerprint to obtain a fingerprint image [3].…”

Human–Machine Interfacing Enabled by Triboelectric Nanogenerators and Tribotronics

“…To realize the functional E‐skin, the flexible tactile sensors are always the basic and essential components . There have been several effective approaches toward the tactile sensors for E‐skin, with the functionalities of large scale, ultrasensitivity, wide range, flexibility, stretchability, and transparency . Alternatively, as an effective mechanosensation device, TENG can easily work as the pressure sensor and hence could naturally be adopted to realize the flexible tactile sensors for E‐skin.…”