Pre-focused lead titanate >25 MHz single-element transducers from hollow spheres

Richard Meyer, Robert Newnham, Sedat Alkoy, Timothy Ritter, Joe Cochran

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Miniature lead titanate (PT) hollow spheres with diameter in the 1 to 10 mm range and wall thicknesses of 20 to 120 μm have been fabricated. Shell sections were used as components of pre-focused transducers. Spheres are produced using a new sacrificial core technique that produces hundreds of spheres with a more uniform wall thickness than those produced by earlier methods. Shells produced from these spheres were found to have a wall thickness variation of about 10%. Despite this variation, bulk properties were estimated from capacitance and impedance data. Shells tested in this work had dielectric constants (1 kHz) near 280 with loss factor of <2% and d33 values of 68 pC/N. Thickness coupling coefficients averaged 0.51 with mechanical quality factors of <15. A transducer fabricated from these sections of spheres had a round-trip insertion loss of -20.1 dB at the center frequency of 39.8 MHz and a 6 dB bandwidth of 33%.

Original languageEnglish (US)
Pages (from-to)488-493
Number of pages6
JournalIEEE transactions on ultrasonics, ferroelectrics, and frequency control
Issue number2
StatePublished - Mar 2001

All Science Journal Classification (ASJC) codes

  • Instrumentation
  • Acoustics and Ultrasonics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Pre-focused lead titanate >25 MHz single-element transducers from hollow spheres'. Together they form a unique fingerprint.

Cite this