Abstract
This report describes the design of a new piezoelectric transducer for round window (RW)-driven middle ear implants. The transducer consists of a piezoelectric element, gold-coated copper bellows, silicone elastomer (polydimethylsiloxane, PDMS), metal cylinder (tungsten), and titanium housing. The piezoelectric element is fixed to the titanium housing and mechanical resonance is generated by the interaction of the bellows, PDMS, and tungsten cylinder. The dimensions of PDMS and the tungsten cylinder with output characteristics suitable for compensation of sensorineural hearing loss were derived by mechanical vibrational analysis (equivalent mechanical model and finite element analysis (FEA)). Based on the results of FEA, the RW piezoelectric transducer was implemented, and bench tests were performed under no-load conditions to confirm the output characteristics. The transducer generates an average displacement of 219.6 nm in the flat band (0.1–1 kHz); the resonance frequency is 2.3 kHz. To evaluate the output characteristics, the response was compared to that of an earlier transducer. When driven by the same voltage (6 Vp), the flat band displacement averaged 30 nm larger than that of the other transducer, and no anti-resonance was noted. Therefore, we expect that the new transducer can serve as an output device for hearing aids, and that it will improve speech recognition and treat high-frequency sensorineural hearing loss more effectively.
Highlights
Various types of middle-ear implant transducers [1,2,3,4,5,6,7,8,9,10] that stimulate round window (RW) have been developed [11,12,13,14,15]
Since the vibration energy spreads to each side of the floating mass transducer (FMT), it cannot transmit all to the RW
Shin and Cho developed a prototype RW transducer by combining a piezoelectric element, cantilever membrane, and bellows [20]. This RW transducer produced mechanical resonance via the cantilever membrane and bellows, so that high output was generated in the mid-frequency band (2–3 kHz)
Summary
Various types of middle-ear implant transducers [1,2,3,4,5,6,7,8,9,10] that stimulate round window (RW) have been developed [11,12,13,14,15]. In order to improve the output characteristics of the low-frequency band, it is important to develop a RW transducer with a new structure. Shin and Cho developed a prototype RW transducer by combining a piezoelectric element, cantilever membrane, and bellows [20] This RW transducer produced mechanical resonance via the cantilever membrane and bellows, so that high output was generated in the mid-frequency band (2–3 kHz). In the sense that one side of the piezoelectric element like previous transducers that “floated” in the sense that one side of the piezoelectric was not completely fixed, thefixed, proposed transducertransducer generates generates vibration in only oneindirecelement was not completely the proposed vibration only tion because one side of the piezoelectric element iselement fixed toisthe bottom the titanium one direction because one side of the piezoelectric fixed to theofbottom of the housing This solves a major of the earlier the anti-resonance-medititanium housing.
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call