Low-frequency reinforced ferroelectric acoustic actuators

This paper reports the low-frequency reinforced ferroelectric acoustic actuators with high performances. In order to achieve a higher output sound pressure level and wider frequency response range, we have proposed the novel rubber/resin bi-layer acoustic diaphragm. From the simulated and measured frequency response results, the ferroelectric acoustic actuators with a rubber/resin bi-layer diaphragm have a first resonant frequency of 630 Hz and an average output sound pressure level of 85 dB@10 cm. These results indicate that the design optimization of acoustic diaphragms can enhance the sound pressure at a low frequency range. Compared to a commercial piezoelectric ceramic speaker with a resin single layer diaphragm, the acoustic actuators fabricated with a rubber/resin bi-layer diaphragm have at least 10 dB higher sound pressure at a low frequency range of less than 1 kHz.