부산대학교 도서관

Matrix transducers have for long been the gold standard in volumetric imaging, and in particular for echocardiography. However, their inner constitution (N 2 elements) accounts for highly dense and individual interconnection of thousands of elements. There are several ways of reducing cable count such as using a micro beamformer or reducing the number of active elements over a wide aperture with a sparse array and also Row Column Addressed (RCA) matrices, which are made of two independent electrode arrays patterned perpendicularly one to each other (2N elements). The latest have recently drawn probes manufacturers attention as there is no need to embed a specific electronic system as for driving a micro beamformer. However, RCA matrices in their raw constitution are not suitable for volumetric echocardiography as a diverging field of view is required and that they only allow for a front axial projection of volume reconstruction. Furthermore, RCA architecture suffers from a lack of true electrical ground and would require dedicated electronic. As to answer this dual issue, a “stack” $(\lambda/4)$ architecture is proposed (patent pending), where the two independent piezoelectric arrays are stacked together with internal common ground. Moreover, instead of using a diverging lens [1] that would account for decreased sensitivity, we suggest a smooth mechanical deformation process achieved through relevant tools and a soft single crystal-based 1–3 piezocomposite materials.