Spatial Correction of an Acoustic Hologram for Reconstructing Surface Vibrations of an Axially Symmetric Ultrasound Transducer

• Published in: Acoustical physics Vol. 68; no. 1; pp. 71 - 82
• Main Authors: Kaloev, A. Z., Nikolaev, D. A., Khokhlova, V. A., Tsysar, S. A., Sapozhnikov, O. A.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.02.2022; Springer; Springer Nature B.V
• Subjects: Acoustic Signals Processing. Computer Simulation; Acoustics; Algorithms; Holograms; Inclination angle; Physics; Physics and Astronomy; Transducers; Ultrasonic imaging; Ultrasonic testing; Ultrasonic transducers; Velocity distribution; acoustic holography; therapeutic multi-element arrays; characterization of ultrasound transducers
• ISSN: 1063-7710; 1562-6865
• DOI: 10.1134/S1063771022010043

A method is proposed for spatially correcting an acoustic hologram recorded on an arbitrarily oriented planar area in front of an axially symmetric ultrasound transducer. The method comprises steps for determining the direction of the transducer’s axis from the measured acoustic hologram, transferring the hologram data on a plane perpendicular to this axis and centering it relative to the axis by means of a correction algorithm that executes appropriate rotations and shifts of the original hologram. The corrected hologram is used for reconstructing the structure of vibrations of the emitting surface of the transducer. A simplified correction algorithm is also considered that is applicable for transducers with narrow angular spectrum and small angles of inclination of the initial hologram to the transducer axis. The accuracy of the developed algorithms is analyzed numerically for a single focusing transducer with a uniform vibrational velocity distribution on its surface and is demonstrated experimentally for an annular 12-element array.