Tutorial - Piezocomposite Transducer Design

Piezocomposite Design/Selection ProcessUltrasound System Design Reality• Most Acoustic Imaging Systems Utilize Piezoelectric Materials inthe Transducers to Generate and Receive the Acoustic Signals• The Transducers Determine the Performance Limits of the Overall System• Transducer Performance is Limited by the Transduction Material Characteristics• Piezocomposite is an Enabling Improvement in Sonar and Ultrasound Transducer PerformanceAdvantages of Piezocomposite Transducers: Imaging Sonars• Increased Sensitivity• Broader Bandwidth– Better resolution• Reduced Sidelobes – Improved image contrast• Improved Impedance Match to Water– Better efficiency– Increased signal to noise• Low Interelement Cross Talk• Greater Element to Element Phase and Amplitude Uniformity• Low Cost Construction1-3 PiezocompositePiezoelectricCeramic RodsPolymer Matrix• Piezoelectric Ceramic Rods in a Polymer Matrix• Model as an Effective Homogeneous Medium• Properties determined by– Piezoelectric Ceramic type– Polymer properties– Volume fraction of Piezoelectric Ceramic (v)Piezocomposite Provides a Large Number of Design Parameters Which can be used to optimize Performance for your ApplicationPiezocomposite Design GoalsParameter Desired ValueCapacitance MaximizeElectrical Impedance Match to SystemAcoustic Impedance Match to ~1.5 MRayls (water)Electromechanical Coupling MaximizeElectrical Loss Tangent MinimizeMechanical Loss (1/Q)MinmizemAny composite ...