Optimizing sparse two-dimensional transducer arrays using an effective aperture approach

We have developed a method for reducing the number of elements in a two-dimensional array while minimizing the loss of image resolution and contrast. The method relies on selecting a different arrangement of elements when the array is transmitting and when the array is receiving energy. The transmit and receive aperture functions are chosen to minimize the difference between the effective aperture of the sparse array and the effective aperture of a desired dense array. The effective aperture is defined by the convolution of the transmit and receive aperture functions. Using this method, we show that the number of elements in a 64×64 two-dimensional array can be reduced by more than six times, and the elements in a 128×128 array can be reduced by more than 12 times, with little effect on the beam forming properties of either array