The design of split row-column addressing array for 2D transducer

Real-time 3D ultrasonic imaging with 2D array is difficult to implement because of the challenge in fabricating and interconnecting the 2D transducer array with a large number of elements. Row-column addressing provides a simple manufacturing method with 2N connections rather than N-2 for an NxN array. The top and bottom electrodes of the transducer are designed to be orthogonal, resulting in essentially two orthogonall-D arrays in a single transducer. However, this interconnection scheme degrades the image quality because of defocusing in column direction in transmit event. To solve this problem, a split row-column addressing (SRCA) scheme is proposed in this paper. Rather than connecting all the elements in the column direction together, the array is divided into several disconnected blocks. This method can access focusing beams in both row and column directions. Selecting an appropriate split scheme is the key to maintaining a reasonable trade off in image quality and the number of connections. The relation between the number of split and the corresponding main-lobe width is discussed. The simulated point spread functions of 32x32 array with and without split row-column addressing are given out. The result shows the image quality is similar to fully addressing for 32x32 array in case of five blocks with 4, 6, 12, 6, and 4 elements of each block.