Use of a Conical Axicon as a Surface Acoustic Wave Focusing Device

Date

1987-1

Author

Atalar, Abdullah
Koymen, Hayrettin

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Ultrasonic axicons generate waves which focus on a line. They are used in various imaging applications as hulk wave focusing devices with a very long depth of focus. A new type of conical axicon is introduced. It consists of a concave parabolic surface immersed in a liquid medium and insonified obliquely by wavefronts generated by a plane transducer. The parabolic cylinder can be approximated by a portion of a circular cylinder without losing significantly in the focusing performance of the axicon. It is also shown that conical axicons can be used to excite surface waves provided that the cone angle of the axicon coincides with the Rayleigh critical angle of the liquid-solid interface. The generated surface waves focus into a diffraction-limited spot. This new surface wave focusing scheme is easy to use and has a conversion efficiency and sensitivity far better than other existing techniques.

Subject Keywords

Acoustics and Ultrasonics, Instrumentation, Electrical and Electronic Engineering

URI

https://hdl.handle.net/11511/52075

Journal

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control

DOI

https://doi.org/10.1109/t-uffc.1987.26911

Collections

Department of Electrical and Electronics Engineering, Article

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Citation Formats

A. Atalar and H. Koymen, “Use of a Conical Axicon as a Surface Acoustic Wave Focusing Device,” IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, pp. 53–63, 1987, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52075.