Title :
High-frequency membrane hydrophone
Author :
Lum, Paul ; Greenstein, Michael ; Grossman, Charles ; Szabo, Thomas L.
Author_Institution :
Hewlett-Packard Labs., Palo Alto, CA, USA
fDate :
7/1/1996 12:00:00 AM
Abstract :
A membrane hydrophone with a 37-/spl mu/m diameter spot poled electrode has been fabricated on a 4-/spl mu/m-thick film of the piezoelectric copolymer, polyvinylidene fluoride trifluoroethylene (PVDF-TrFE), and initially characterized. The hydrophone has an effective spot size of less than 100 /spl mu/m, an on-membrane +7-dB gain buffer amplifier, and a -3-dB bandwidth of 150 MHz. The acoustic properties of the hydrophone were investigated with a transducer equivalent circuit model, the electric fringe fields due to poling were characterized with a finite difference electrostatic field model, and the effective spot diameters 2a/sub 3/ and 2a/sub 6/ were estimated. Measurements on the bandwidth, effective spot size, and sensitivity are presented. This hydrophone appears suitable for the characterization of both the frequency and spatial parameters of high-frequency transducers such as intravascular ultrasound (IVUS) catheter transducers operating in the 10-40 MHz range.
Keywords :
biomedical equipment; biomedical ultrasonics; hydrophones; ultrasonic transducers; -3 dB; 10 to 40 MHz; 150 MHz; 37 mum; 4 mum; 7 dB; effective spot size; electric fringe fields; high-frequency membrane hydrophone; intravascular ultrasound catheter transducers; medical acoustic imaging; piezoelectric copolymer film; poling; polyvinylidene fluoride trifluoroethylene; sensitivity; spot poled electrode; transducer equivalent circuit model; Acoustic transducers; Bandwidth; Biomembranes; Electrodes; Equivalent circuits; Finite difference methods; Piezoelectric films; Piezoelectric transducers; Sonar equipment; Ultrasonic transducers;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
