3-D synthetic imaging using 128-channel 2-D sparse CMUT array

Bio-medical ultrasound imaging has recently gained considerable attention. A two-dimensional (2-D) array is essential for three-dimensional (3-D) volumetric imaging. Fully populated 2-D dense array requires thousands of active elements and their interconnections. We present a 2-D CMUT sparse array with 128 elements for 3-D volumetric imaging. This CMUT sparse array with a die size of 6.3 mm × 6.3 mm consists of 128 elements, which has 24 μm cells arranged in a 3×3 configuration. This work aims to construct a classical synthetic aperture imaging system, which is one of the imaging methods that use several channels. A switch separates the transmission part from the receiving part, and is controlled by the digital signal of the data acquisition. To measure the point spread function of the synthetic imaging system, imaging experiments were performed on thin wire phantom objects. In this paper, we present a 2-D synthetic imaging system with a switching channel to reduce the system complexity and minimize the cost.