Study on Discontinuity Properties of Phased-Array Ultrasound Transducer Affecting to Sound Pressure Fields Pattern

The phased-array ultrasound transducer types are
utilities for medical ultrasonography as well as optical imaging.
However, their discontinuity characteristic limits the applications due
to the artifacts contaminated into the reconstructed images. Because
of the effects of the ultrasound pressure field pattern to the echo
ultrasonic waves as well as the optical modulated signal, the side
lobes of the focused ultrasound beam induced by discontinuity of the
phased-array ultrasound transducer might the reason of the artifacts.
In this paper, a simple method in approach of numerical simulation
was used to investigate the limitation of discontinuity of the elements
in phased-array ultrasound transducer and their effects to the
ultrasound pressure field. Take into account the change of ultrasound
pressure field patterns in the conditions of variation of the pitches
between elements of the phased-array ultrasound transducer, the
appropriated parameters for phased-array ultrasound transducer
design were asserted quantitatively.

• Tran Trong Thang
• Nguyen Phan Kien
• Trinh Quang Duc

• Phased-array ultrasound transducer
• sound pressure pattern
• discontinuous sound field
• numerical visualization.

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