Abstract: In order to improve the quality of ultrasonic images, it is necessary to narrow the width of the ultrasonic beam produced by the imaging transducer. At the same time, the side lobes of the beam should be suppressed in order to prevent their interference with the main imaging lobe of the beam. Apodization can be used to narrow beam width of an ultrasonic imaging array. While this effect has been produced through element amplitude weighting in pulsed mode linear arrays, a simpler method of apodization can be achieved simply by fabricating elements into other geometries. Currently, small rectangular elements are the standard shape used in single-dimensional ultrasonic imaging arrays. By fabricating array elements into other shapes, apodization is placed on the array. Various apodization schemes have been modeled using a computer simulation. Using the model results, 6 MHz single element transducers were constructed from lead zirconate titanate (PZT) in various geometries. All of these elements had equal surface area. Each of these elements were diced using a common silicon wafer dicing saw as is the preferred industry method for producing ultrasonic arrays. Beam patterns from these transducers were compared to the modeled results. !2
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