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(a) A front view sketch of the existing 256-element array with a compact 16-spirals layout of circular elements. (b) 364-element capacity-constrained tessellation array with elements shaped as spherical polygons. The two arrays have the same parameters: 1.5 MHz frequency, 144 mm aperture, 120 mm focal length, 38.5 mm2 area of each element, 0.5 mm gap between the elements, and 50 mm central opening for imaging probe.
