Three dimensional (3D) ultrasound imaging is becoming a standard mode for medical ultrasound diagnoses.
Conventional 3D ultrasound imaging is mostly scanned either by using a two dimensional matrix array or by motorizing
a one dimensional array in the elevation direction. However, the former system is not widely assessable due to its cost,
and the latter one has limited resolution and field-of-view in the elevation axis. Here, we propose a 3D ultrasound
imaging system based on the synthetic tracked aperture approach, in which a robotic arm is used to provide accurate
tracking and motion. While the ultrasound probe is moved by a robotic arm, each probe position is tracked and can be
used to reconstruct a wider field-of-view as there are no physical barriers that restrict the elevational scanning. At the
same time, synthetic aperture beamforming provides a better resolution in the elevation axis. To synthesize the
elevational information, the single focal point is regarded as the virtual element, and forward and backward delay-andsum
are applied to the radio-frequency (RF) data collected through the volume. The concept is experimentally validated
using a general ultrasound phantom, and the elevational resolution improvement of 2.54 and 2.13 times was measured at
the target depths of 20 mm and 110 mm, respectively.
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