We have described an electronically focused and scanned acoustic imaging device in earlier papers.1,2 This device was constructed by using a tapped acoustic surface wave delay line as a phase reference for an array of piezoelectric transducers. By inserting a frequency modulated chirp along the delay line, the device can be used either as a receiver or as a transmitter. In the transmit mode, it acts like a moving lens, emitting a focused beam which scans along a plane parallel to the array at a velocity comparable to the acoustic velocity. The same array can be used in the receive mode. By this means, a B-scan device was constructed which has good transverse and range definition..
KeywordsDelay Line Side Lobe Main Lobe Chirp Signal Side Lobe Level
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- 1.J. Fraser, J. Havlice,G. Kino, W. Leung, H. Shaw, K. Toda, T. Waugh, D. Winslow, and L. Zitelli, “A Two-Dimensional Electronically Focused Imaging System,” presented at the IEEE Group on Sonics and Ultrasonics Symposium, November 11 - 14, 1974.Google Scholar
- 2.J. Fraser, J. Havlice, G. Kino, W. Leung, H. Shaw, K. Toda, T. Waugh, D. Winslow, and L.;Zitelli, “An Electronically Focused Two-Dimensional Acoustic Imaging System,” Acous-tical Holography, edited by Newell Booth; Vol. 6, 1975, pp. 275.-304.Google Scholar
- 3.J. Souquet, Ph.D. Thesis, Stanford University, Stanford, California (1976)Google Scholar