volume | PIER Journals

Abstract

Traditional touchscreens, popular for their adaptability and ease of maintenance, typically use capacitive technology where finger contact alters an electrostatic field. Here we demonstrate a touch keyboard configuration, based on a resonant-based system encompassing split-ring resonators (SRRs). These resonators, operating at the GHz spectral range, detect a finger's proximity, changing resonance frequency, but remain unaffected by distant objects - thus allowing for a parallel and independent readout of multiple keys. Specifically, 14 independent keys have been demonstrated, and the frequency-sharing protocol for parallel acquisition of sequences has been successfully implemented. The readout is performed in parallel by monitoring the transmission through a microstrip line, which is equipped with a series of distinct SRRs that resonate at different frequencies. The system has been implemented on an extremely low-cost platform, which can be transformative for similar tasks.

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Dr. Vladyslav Tkach

Dr. Mykola Khobzei

Dr. Serhii Haliuk

Dr. Ihor Safronov

Dr. Andrii Samila

Prof. Vjaceslavs Bobrovs

Dr. Dmytro Vovchuk