Yintang Yang

Conflicts of Interest The authors declare no conflicts of interest. Data Availability Statement The data that support the funding of this work are available from the corresponding author upon reasonable request. References 1 and , “0.13-μm CMOS Phase Shifters for X-, Ku-, and K-Band Phased Arrays,” IEEE Journal of Solid-State Circuits 42, no. 11 (2007): 2535–2546.

Abstract Focused high-frequency acoustic waves are utilized in industrial non-destructive testing (NDT) on account of their exceptional spatial resolution and high sensitivity. However, the majority of the focusing methods currently adopted for high-frequency transducers are mechanical pressure focusing and lens focusing, which may inflict mechanical damage on piezoelectric elements and give rise to low transmission efficiency.

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