Title :
Avoiding diffraction grid effect in ultrasonic fields of 1-3 PZT polymer piezocomposite transducers
Author :
Núñez, Ismael ; Negreira, Carlos
Author_Institution :
Fac. de Ciencias, Inst. de Fisica, Montevideo, Uruguay
fDate :
3/1/1999 12:00:00 AM
Abstract :
Improvement of sensitivity in ultrasonic fields of piezocomposite transducers is limited because of diffraction effects arising from the periodic structure. We present a theoretical and experimental study of ultrasonic fields of 1-3 PZT polymer piezocomposite transducers. The relation between the composite grid periodicity and the wavelength is critical in order to obtain a far field similar to that of homogeneous transducers. If diffraction grid effect is present, it results in an important energy loss in the higher diffraction orders. These higher orders perturb the central field of the transducer because of multipath contributions to the main lobe caused by reflections from the boundaries of the test sample.
Keywords :
acoustic field; filled polymers; lead compounds; piezoelectric transducers; ultrasonic diffraction; ultrasonic transducers; PZT; PZT polymer piezocomposite transducer; PbZrO3TiO3; diffraction grid effect; energy loss; periodic structure; sensitivity; ultrasonic field; Acoustic emission; Acoustic propagation; Acoustic transducers; Bioceramics; Diffraction; Electrical capacitance tomography; Frequency; Piezoelectric transducers; Polymers; Ultrasonic transducers;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on