Fully sampled, 3600 element, two dimensional transducer array for low cost C-scan imaging

摘要

Preliminary results relating to the design, fabrication, and characterization of a 3600 (60 x 60) element, fully sampled, 5 MHz two dimensional (2D) array are presented. The viable element yield of the new array was estimated at 98.3%. Single-element pulse-echo experiments indicate that the center frequency is 4.7 MHz - 7.8% below the resonant frequency determined by Finite Element Analysis (FEA) simulation. Pulse-echo signal fractional bandwidth was measured to be 60.3% at the -6 dB level. Ringdown was longer than anticipated in experimental pulse echo voltage waveforms, which we attribute in part to a lack of matching layer and a low-loss backing material. Based on plane-wave pulse-echo experiments in a water-tank, single element signal-to-noise ratio (SNR) was calculated to be 6.0 when using a plane-wave transmit (all elements excited). Experimental angular beam patterns were more directional than predicted with the standard soft-baffle equation, but in good agreement with FEA simulations that take account of finite acoustic crosstalk.