Due to its additional frequency response,dual-frequency ultrasound has advantages over conventional ultrasound,which operates at a specific frequency band.Moreover,a tunable frequency from a single transducer enables ...Due to its additional frequency response,dual-frequency ultrasound has advantages over conventional ultrasound,which operates at a specific frequency band.Moreover,a tunable frequency from a single transducer enables sonographers to achieve ultrasound images with a large detection area and high resolution.This facilitates the availability of more advanced techniques that simultaneously require low-and high-frequency ultrasounds,such as harmonic imaging and image-guided therapy.In this study,we present a novel method for dual-frequency ultrasound generation from a ferroelectric piezoelectric micromachined ultrasound transducer(PMUT).Uniformly designed transducer arrays can be used for both deep low-resolution imaging and shallow high-resolution imaging.To switch the ultrasound frequency,the only requirement is to tune a DC bias to control the polarization state of the ferroelectric film.Flextensional vibration of the PMUT membrane strongly depends on the polarization state,producing low-and high-frequency ultrasounds from a single excitation frequency.This strategy for dual-frequency ultrasounds meets the requirement for either multielectrode configurations or heterodesigned elements,which are integrated into an array.Consequently,this technique significantly reduces the design complexity of transducer arrays and their associated driving circuits.展开更多
基金supported by the Samsung Research Funding&Incubation Center for Future Technology(Grant No.SRFC-MAI702-03)National Research Foundation of Korea(NRF)Grant funded by the Ministry of Science and ICT(grant no.NRF2020M3D1A2101933)supported by the Korea Medical Device Development Fund grant funded by the Korean government(the Ministry of Science and ICT)(Project no.1711196544)。
文摘Due to its additional frequency response,dual-frequency ultrasound has advantages over conventional ultrasound,which operates at a specific frequency band.Moreover,a tunable frequency from a single transducer enables sonographers to achieve ultrasound images with a large detection area and high resolution.This facilitates the availability of more advanced techniques that simultaneously require low-and high-frequency ultrasounds,such as harmonic imaging and image-guided therapy.In this study,we present a novel method for dual-frequency ultrasound generation from a ferroelectric piezoelectric micromachined ultrasound transducer(PMUT).Uniformly designed transducer arrays can be used for both deep low-resolution imaging and shallow high-resolution imaging.To switch the ultrasound frequency,the only requirement is to tune a DC bias to control the polarization state of the ferroelectric film.Flextensional vibration of the PMUT membrane strongly depends on the polarization state,producing low-and high-frequency ultrasounds from a single excitation frequency.This strategy for dual-frequency ultrasounds meets the requirement for either multielectrode configurations or heterodesigned elements,which are integrated into an array.Consequently,this technique significantly reduces the design complexity of transducer arrays and their associated driving circuits.
