One of the core technologies for wearable electronics is the use of an interactive display device that is attached to the body or clothes to transmit various bio-signals and environmental stimuli to the user. In this study, we report a flexible audiovisual display device consisting of a polyvinylidene difluoride (PVDF) thin-film speaker stacked on an 8 × 8 array of quantum-dot light-emitting diodes (QD-LEDs) and a multi-functional sensor consisting of temperature and ultraviolet (UV) sensors connected to a pressure sensor, allowing the body temperature and UV exposure to be displayed both visually and acoustically. Polydimethylsiloxane is employed as an insulator between the carbon nanotube (CNT)/polyaniline temperature sensor and the ZnO/CNT UV sensor to form a capacitor-type pressure sensor. With the use of a stretchable polymer substrate, liquid metal Galinstan interconnections, and the flexible Au-grid electrodes, both the PVDF speaker and the QD-LED array are stable under repeated cycles of bending deformation with a bending radius of 7.5 mm. By connecting the audiovisual display device to the skin-attached multi-functional sensor, changes in the body temperature and UV exposure are displayed as LED patterns with accompanying acoustic alarms. This study demonstrates the significant potential of our proposed audiovisual monitoring device and multi-functional sensor for use in health-monitoring applications, especially for the elderly and infants requiring prompt care.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean Government (MSIT) (grant nos. NRF-2022R1A4A1031687, NRF-2019R1A2B5B03069545, and NRF-2022R1A2C2092575). The authors also thank the KU-KIST graduate school program of Korea University.
© 2022 American Chemical Society.
- audiovisual display
- flexible QD-LED array
- interactive system
- multi-functional sensor
- PVDF thin-film speaker
ASJC Scopus subject areas
- General Materials Science