Optimized Backing Layers Design for High Frequency Broad Bandwidth Ultrasonic Transducer

Area of Science:

• Medical Imaging
• Materials Science
• Acoustics

Background:

• Broad bandwidth in ultrasonic transducers is crucial for high axial resolution and clinical imaging flexibility.
• Limitations in spatial resolution due to bandwidth are a significant challenge in ultrasound medical imaging.
• Acoustic impedance matching is a common technique to achieve broad bandwidth and high resolution.

Purpose of the Study:

• To propose an optimized backing layer design for ultrasonic transducers to broaden bandwidth.
• To investigate the effect of a tunable acoustic impedance matching layer of backing (AIMLB) on transducer bandwidth.
• To enhance the performance and imaging capability of 20-MHz ultrasonic transducers.

Main Methods:

• Utilized the Mason equivalent circuit method to analyze backing material effects on transducer bandwidth.
• Employed finite-element method simulations using PZFlex software for transducer optimization.
• Fabricated a 20-MHz ultrasonic transducer incorporating the optimized AIMLB.

Main Results:

• The optimized transducer design with AIMLB achieved a broad bandwidth of approximately 92.29%.
• Experimental results closely matched the PZFlex simulation predictions.
• The fabricated transducer demonstrated high performance and good ultrasonic imaging capability.

Conclusions:

• The addition of an acoustic impedance matching layer of backing (AIMLB) effectively broadens transducer bandwidth.
• The optimized transducer design significantly improves axial resolution and imaging quality.
• This advancement holds promise for enhanced clinical ultrasound applications.