Experimental Characterization of A Piezoelectric Transducer Array Taking into Account Crosstalk Phenomenon

Abstract

Ultrasonic transducer arrays are generally composed of several piezoelectric elements arranged in 1D or 2D ways. Crosstalk is an undesirable phenomenon decreasing the performance of these devices. It generates parasitic displacements at the elements' radiating surfaces, which changes the directivity of the array. Furthermore, the transducer's displacement plays a critical role in terms of the focal area and transferred intensities. The objective of this paper is to characterize a piezoelectric array composed of seven-elements made of PZ 27 ceramic experimentally. It investigates the effects of the crosstalk phenomenon on the array's performance in particular. The results have shown that the array's elements vibrate mainly in thickness mode, but the displacement is not uniform along their length due to the contribution of a parasitic length mode. Moreover, the major parasitic displacements are obtained on the neighboring passive elements: about -7.3 dB, -11 dB, and -12 dB, on the first, the second, and the third elements, respectively.

Investigation of the electrical limit conditions effects in piezoelectric transducer arrays utilized in medical imaging

“…Furthermore, in our previous work (ref. 8), it was also demonstrated numerically and experimentally that the influence and the contribution of these undesirable modes (width and length modes) is negligible. The transducer array radiates in a fluid medium (water in medical imaging applications) meshed with isoparametric quadratic elements respecting the λ/4 criterion.…”

“…In other words, this method supposes the displacement uniform at the surface of the individual elements, which is not true. For more precision, it would be better to measure the displacement at the whole surface of the array elements, to take into account the contribution of the parasitic length mode [8,16]. The latter makes the displacement not uniform.…”

“…The major objective of ongoing and future research in this area is to optimize the electroacoustic performance of these transducers, to obtain a high image resolution for more reliable and safe diagnostics. For this purpose, several works investigate the crosstalk phenomenon, which decreases the performance of the ultrasonic transducer arrays [6][7][8][9][10][11][12][13][14]. Indeed, when one element of a transducer array is driven, it generates parasitic voltages and/or displacement fields on the passive neighboring elements, which affects the performance of these devices.…”

A Tiled Ultrasound Matrix Transducer for Volumetric Imaging of the Carotid Artery

“…Since our measurement setup and transducer configuration do not allow us to measure the crosstalk directly, we analyzed the possible effects of both electrical and acoustical crosstalk on the directivity pattern via simulations. For this, we used the ultrasound simulator FOCUS, as explained previously (see Table 1), to simulate the directivity pattern of the transducer elements excited with different amplitudes and time delays to mimic the crosstalk [54,55]. In all simulations, we used an array of 31 elements with the active element being the central one.…”