Acoustic Switching Ratios of Piezoelectric and Electrostrictive Oats

  • Khalid Azim
  • Keith Wang
Part of the Acoustical Imaging book series (ACIM, volume 9)


The conventional piezoelectric Opto-Acoustic Transducer (PEOAT) has been studied theoretically and experimentally. The results indicate that due to the characteristics of the present photoconductive layer the Acoustic Switching Ratio (ACSWR) in the megahertz range of frequencies is in general inadequate for beam focusing or beam shaping applications. The physical properties of the present photoconductive layer must be successfully altered to bring about an improvement in the acoustic switching ratio.

We have recently started work on an alternative approach towards improving the ACSWR. This approach involves the use of an electrostrictive layer in the place of the piezoelectric layer in previous OATs. Electrostrictive layers have been prepared from some commercially available powders with very high dielectric constants. With these layers electrostrictive OATs (ESOATs) have been built. Preliminary experimental measurements indicate improved ACSWR and demonstrate the potential usefulness of this new class of OATs.


High Dielectric Constant Piezoelectric Layer High Frequency Field Acoustic Output Switching Ratio 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    K. Wang and Glen Wade, “A Scanning Focused Beam System for Real-Time Diagnostic Imaging,” Acoustical Holography, Vol. 6, N. Booth, Ed., p. 213 (1975).Google Scholar
  2. 2.
    C. Sabet and C. W. Turner, “Parameteric Transducer for High Speed Real-Time Acoustic Imaging,” Electronics Letters, 22nd January 1976, Vol. 12, No. 2, p. 44.ADSCrossRefGoogle Scholar
  3. 3.
    Keith Wang, Vance Burns, Glen Wade and Scott Elliot, “Opto-Acoustic Transducers for Potentially Sensitive Ultrasonic Imaging,” Optical Engineering, September/October 1977, Vol. 16, No. 5, p. 432.ADSGoogle Scholar
  4. 4.
    T. Hu, Luis Basto and Keith Wang, “A Potential High Performance Ultrasonic Imaging System,” Record of Conference Papers, 1978 IEEE Region Five Annual Conference, p. 206.Google Scholar
  5. 5.
    S. Elliott, G. Wade, T. Hu and K. Wang, “Characteristics of Opto Acoustic Transducers,” 1978 Ultrasonics Symposium Proceedings, p. 250.Google Scholar
  6. 6.
    K. Azim, K. Wang and K. Bates, “Recent Investigations on OAT Structures,” 1979 Ultrasonics Symposium Proceedings (to be published).Google Scholar
  7. 7.
    Ken Bates and Keith Wang, “PEOATs and ESOATs,” 1979 Ultrasonics Symposium Proceedings (to be published).Google Scholar
  8. 8.
    S. Elliot, V. Domarkas and Glen Wade, “Frequency Characteristics of Opto-Acoustic Transducers,” IEEE Transactions on Sonics and Ultrasonics Vol. SU-25, No. 6, November 1978, p. 346.CrossRefGoogle Scholar
  9. 9.
    Jaffe, Cook and Jaffe, Piezoelectric Ceramics (Academic Press, 1971).Google Scholar
  10. 10.
    K. N. Bates, “A Highly Electrostrictive Ceramic,” 1977 Ultrasonics Symposium Proceedings, p. 393.Google Scholar
  11. 11.
    K. Iamsakun, W. Elder, C. D. W. Wilkinson and R. M. De La Rue, “Surface Acoustic Wave Devices Using Electrostrictive Transduction,” J. Phys. D: Appl. Phys., Vol. 8, p. 266 (1975).ADSCrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • Khalid Azim
    • 1
  • Keith Wang
    • 1
  1. 1.Department of Electrical EngineeringUniversity of HoustonHoustonUSA

Personalised recommendations