[2] [2] FANG H J,CHEN Y,WONG C M,et al, Anodic aluminum oxide-epoxy composite acoustic matching layers for ultrasonic transducer application[J]. Ultrasonics,2016,70:29-33,

[3] [3] WANG Yulei,TAO Jingya,GUO Feifei,et al, Magnesium alloy matching layer for high-performance transducer appli-cations[J]. Sensors,2018,18(12):4424,

[4] [4] YANG H C, Development of novel 1-3 piezocom-posites for low-crosstalk high frequency ultrasound array transducers[D]. Los Angeles,USA:University of Southern California，2012,

[5] [5] CELMER M,OPIELINSKI K J,DOPIERAA M, Structural model of standard ultrasonic transducer array developed for FEM analysis of mechanical crosstalk[J]. Ultrasonics,2018,83:114-119,

[6] [6] CHA J H,CHANG J H, Development of 15 MHz 2-2 piezo-composite ultrasound linear array transducers for ophthalmic imaging[J]. Sensors and Actuators A:Physical,2014,217:39-48,

[7] [7] SHUNG K K, Diagnosticultrasound-imaging and blood flow measurements[M]. 2nd ed, Los Angeles,USA:CRC Press,2014:39-101,