Microwave Theremin Piano: SRR-Based Touchpad
Progress in Electromagnetics Research Letters 2025
Vladyslav Tkach, Mykola Khobzei, Serhii Haliuk, Ihor Safronov, Andrii Samila, Vjačeslavs Bobrovs, Dmytro Vovchuk

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.


Keywords
Computer keyboard substitutes (disability aids); Loudspeakers; Magnetic moments; Microwave resonators; Natural frequencies; Readout systems; Ring gages
DOI
10.2528/PIERL24080404
Hyperlink
https://www.jpier.org/PIERL/pier.php?paper=24080404

Tkach, V., Khobzei, M., Haliuk, S., Safronov, I., Samila, A., Bobrovs, V., Vovchuk, D. Microwave Theremin Piano: SRR-Based Touchpad. Progress in Electromagnetics Research Letters, 2025, Vol. 123, pp.89-94. ISSN 1937-6480. Available from: doi:10.2528/PIERL24080404

Publication language
English (en)
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